Xenograft model for identifying chemotherapeutic agents against papillomaviruses

The report describes the establishment and characterization of a mouse xeno graft transplantation model for the study of papillomavirus infection of bo vine skin. Calf scrotal skin was inoculated with bovine papillomavirus type 2 before grafting it to the dorsum of severe combined immunodeficient mice . The grafted skin contained epidermis, dermis, and a thin layer of fat. Af ter 5 months the induced warts not only showed histological features of pap illomavirus infections but also tested positive for viral DNA and papilloma virus capsid antigen. The formation of infectious virions was demonstrated by inoculation of new transplants with crude extract from the induced warts as well as in a cell culture focus assay. Topical application of bromoviny l-2'-deoxyuridine led to a reduction in viral DNA content in the developing wart. This small-animal xenograft model should be useful for characterizin g antiviral compounds and providing an understanding of the regulation of p apillomavirus infections.