Cytokeratin 18, Alexa Fluor 488, clone: LDK18, eBioscience™

Description

Cytokeratins are a subfamily of intermediate filament proteins and are characterized by a remarkable biochemical diversity, represented in human epithelial tissues by at least 20 different polypeptides. They range in molecular weight between ∽40kDa and ∽68kDa and isoelectric pH between 4.9 - 7.8. The individual human cytokeratins are numbered 1 to 20. The various epithelia in the human body usually express cytokeratins which are not only characteristic of the type of epithelium, but also related to the degree of maturation or differentiation within an epithelium. 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 18 (Keratin 18, KRT18, type I cytoskeletal 18) belongs to the type A (acidic) subfamily of low molecular weight keratins, exists in combination with cytokeratin 8. Tissues from gastrointestinal tract, respiratory tract and urogenital tract, as well as endocrine and exocrine tissues and mesothelial cells are positive for cytokeratin 18. Further, cytokeratin 18 is found primarily in non-squamous epithelia and is present in a majority of adenocarcinomas and ductal carcinomas, but not in squamous cell carcinomas. Hepatocellular carcinomas express only cytokeratins 8 and 18. Mutations in the cytokeratin 18 gene have been linked to cryptogenic cirrhosis. Two transcript variants encoding the same protein have been found for the cytokeratin 18 gene. Cytokeratin subtype expression patterns are used to an increasing extent in the distinction of different types of epithelial maligcies. 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.