Localization of papillomavirus and virus-specific antigens in the skin of tumor-bearing Mastomys natalensis (GRA Giessen). 
In skin neoplasms (so-called keratoakanthomas, papillomas, and squamous cell carcinomas) of Mastomys natalensis (GRA Giessen) virus particles and viral antigens were demonstrated in distinct epithelial layers.  Nuclei of the upper parts of the stratum granulosum and disintegrated cell parts of the stratum corneum contain viral structures.  The localization of virus particles and viral antigens in any skin neoplasms of M. natalensis (GRA Giessen) corresponded to the sites where papillomavirus-specific material had been demonstrated in papillomas of other species.