anti-Cytokeratin-19 (human), Rabbit Monoclonal (RM364)

Cytokeratins are keratin proteins found in the intracytoplasmic cytoskeleton of epithelial tissue (at least 20 different polypeptides). They are an important component of intermediate filaments, which help cells resist mechanical stress. Expression of these cytokeratins within epithelial cells is largely specific to particular organs or tissues. The subsets of cytokeratins which an epithelial cell expresses depends mainly on the type of epithelium, the moment in the course of terminal differentiation and the stage of development. Thus a specific cytokeratin expression profile allows the identification of epithelial cells. Furthermore, this applies also to the malignant counterparts of the epithelia, (carcinomas). Cytokeratin subtype expression patterns are used to an increasing extent in the distinction of different types of epithelial malignancies. The cytokeratin antibodies are not only of assistance in the differential diagnosis of tumors using immunohistochemistry on tissue sections, but are also a useful tool in cytopathology and flow cytometric assays. Cytokeratin-19 is a type I cytokeratin. The type I cytokeratins consist of acidic proteins which are arranged in pairs of heterotypic cytokeratin chains. Unlike its related family members, this smallest known acidic cytokeratin is not paired with a basic cytokeratin in epithelial cells. It is specifically found in the periderm, the transiently superficial layer that envelops the developing epidermis. Cytokeratin-19 is often used together with cytokeratin-8 and cytokeratin-18 to differentiate cells of epithelial origin from hematopoietic cells in tests that enumerate circulating tumor cells in blood.