Immunofluorescent studies of epidermal protein during UV induced carcinogenesis

Previous studies with agar diffusion technique demonstrated that antibodies produced in rabbits by injection of urea extractable proteins of rat cornfied cells cross react with proteins extracted from normal epidermis of hairless mice using the same technique. In the present study we investigated by indirect immunofluorescence microscopy the immunoreactivity of epidermal proteins in normal and ultraviolet light (UVB) induced hyperplasia and malignant transformation. Reactivity to the antibody was seen over the entire epidermis of nontreated skin and hypertrophied epidermis which occurred at 6-8 weeks after initiation of UVB irradiation. However, the reactivity diminished when malignant changes took place in the epidermal cells. Almost complete disappearance of the immunoresponse was observed in squamous cell carcinoma produced by further UVB radiation. These results suggest that the reactivity of this urea extractable protein serves as an additional immunologic marker for normal epidermal cells. Alterations in the immunoreactivity parallels UVB induced carcinogenesis.