Ks 19.1 represents an excellent marker to discriminate glandular epithelial carcinoma from those of different origin. No reaction with hepatocellular carcinoma. Polypeptide reacting: Mr 40 000 polypeptide (keratin K19; formerly also designated cytokeratin 19) of human glandular epithelia. he epitope has been localized on aa. 317-333(KAALEDTLAETEARFKS) of the alpha-helical fragment.Involved in the organization of myofibers. Together with KRT8, helps to link the contractile apparatus to dystrophin at the costameres of striated muscle.