Keratin expression in epidermolysis bullosa simplex (Dowling-Meara).

The Dowling-Meara variant of epidermolysis bullosa simplex (EBS) is characterized microscopically by clumping of the keratin tonofilaments within areas of incipient blistering, thereby raising the possibility that an abnormality of the keratin cytoskeleton might underlie blister formation in this condition. In order to investigate keratin expression in Dowling-Meara EBS, the staining profile of a panel of antikeratin monoclonal antibodies was examined in perilesional skin from 5 affected subjects, using a standard immunoperoxidase technique. Normal labelling characteristics were demonstrated by antibodies identifying keratins of the basal and suprabasal compartments of normal interfollicular epidermis and of simple epithelia (keratin 19). In addition, a keratin expressed in hyperproliferative epidermal states was shown to be absent. The results suggest that the profile of keratin synthesis is normal in Dowling-Meara EBS and that the tonofilament clumping may be, therefore, the result of a post synthetic modification of keratin molecules.