Purified anti-Cytokeratin 18

Keratin 18 (also know as cytokeratin 18) is a 48 kD member of the Type I intermediate filament family, that forms heterotetramers. Keratin 18 is widely expressed in normal single layer epithelial tissues (liver, pancreas) and is expressed at high levels in some tumor tissues. Keratin 18 and filament partner keratin 8 are the most common members of intermediate filament family. Mutations in keratin 18 have been linked to cryptogenic cirrhosis. This protein is induced by retinoic acid, estrogen (breast cancer cells), and the Ras-signaling pathway (Ha-Ras, activated Src, Lck, Raf). Keratin 18 can be modified by phosphorylation, glycosylation, and ubiquitination. The active heterotetramer consists of two type I and two type II keratins (type I is acidic 40-55 kD, type II is neutral to basic 56-70 kD). Keratin 18 has been shown to associate with keratin 8, Mrj (a DnaJ/HSP40 family protein), and Hsp70. The Poly6172 antibody recognizes human and mouse keratin 18 and is useful for Western blotting.