Cytokeratins in the canine epidermis

The purpose of this study was to characterize the cytokeratins (CKs) presen t in the clinically normal skin of dogs. Skin samples from five German shep herds, five Boxers, five Cocker spaniels, five Yorkshire terriers and five mongrels were examined biochemically (using gel electrophoresis and western blotting) and immunohistochemically (using a alkaline phosphatase anti-alk aline phosphatase technique). Results indicated that the canine epidermis e xpressed the cytokeratins 1, 5, 6, 10/11, 14 and 16. There were no consiste nt differences in CK expression between the examined breeds with the except ion of an individual polymorphism in CK1 and CK10/11. Immunohistochemical s tudies showed CK 14 labelling of the basal cell layer whereas CK10/11 stain ing was seen in the suprabasal cell layer of epidermis. Surprisingly, expre ssion of CK6. known as 'stress' cytokeratin. was demonstrated in all epider mal samples. These results indicate that there is a striking consistency of cytokeratin expression in different breeds which should be useful in the i nvestigation and characterization of canine skin diseases.