Abstract
Canine oral papilloma virus (COPV) has been known to possess strict host and tissue specificities. The present study was undertaken to ascertain the oncogenic potential of COPV in a variety of tissues and organs of dogs. Inoculation with a phosphate butfered saline suspension of experimentally produced oral papillomas into the conjunctival epithelium of the eyeball induced tumors at the site of inoculation in 8 of 17 dogs. These tumors began to develop after an incubation period from 45 to 60 days, and attained maximum growth in 2 weeks. The general histological characteristics of the eye tumor were similar to those of oral papilloma. The lesions recovered spontaneously. With the filtrate of eye tumor emulsion, oral papillomas were induced in the oral mucosa of young dogs. Papillomatous tumors were also induced experimentally in the eyelid and skin. When administered with chemical carcinogen (MNNG), papilloma-bearing dogs showed a prolonged course of papilloma. Discussion was made on the progress of virus-induced papillomas. In the course of the present experiment, a 5-year-old male mongrel dog was found to have spontaneous multiple growth of papillomatous tumors in the mucous membrane of the lips and right eyelid. Histologically, the tumors in these organs were papillomas and contained papilloma virus-like particles.
