Changes of cytokeratin expression in the epidermis with chronic venous insufficiency

A specific, individual pattern of cytokeratins (Cks) is expressed by each epithelial cells as part of the cytoskeleton. Cks are established as markers of epidermal differentiation. Basal cells are characterized by CK5 and 14 expression, whereas CK 1, 10 and 11 are typical for the suprabasal compartment of normal epidermis. Here, we investigated changes of Pan-CK, CK 10, and CK 14 expression in the epidermis in various stages of chronic venous insufficiency (CVI).

In punch biopsies of 24 patients with chronic venous insufficiency and of 6 volunteers with normal skin Cks were detected by indirect immunofluorescence using monoclonal antibodies against CK 10, CK 14 and Pan-CK.

CK 10 and Pan-CK staining intensity increased with the severity of CVI changes. Suprabasal cells showed an upregulation of CK 10 and Pan-CK expression first in venous eczema. CK 14 expression is under normal condition confined to the basal cell layer of the epidermis. However in venous eczema and lipodermatosclerosis, CK 14 is detected in the suprabasal epidermal compartment.

It is therefore concluded that altered differentiation and stratification mechanisms occur in keratinocytes in the epidermis with CVI first detectable in the stage of venous eczema. These changes are accompanied by a characteristic CK expression pattern.