Immunohistochemical Demonstration of Poly(Adenosine Diphosphate-Ribose) Synthesis in Human Skin

The study investigated the distribution of poly(ADP-ribose) synthesis in human skin using an indirect immunofluorescence technique. In normal skin, poly(ADP-ribose) was observed in the nuclei of epidermal and dermal cells, including hair follicles and sweat glands. The presence of NAD intensified this immunofluorescence. In psoriatic skin, the pattern was similar to normal skin, but fluorescence was also seen in the parakeratotic horny layer. In cancerous skin, weak fluorescence was noted in the inner layers of horn pearls in squamous cell carcinoma, while strong fluorescence was observed in the outer layers and in tumor cells of malignant melanoma and basal cell epithelioma. These findings suggested a link between poly(ADP-ribose) synthesis and epidermal cell differentiation.