Feline papillomas and papillomaviruses

Area of Science:

• Veterinary Virology
• Dermatology
• Oncology

Background:

• Papillomaviruses (PVs) are known pathogens of stratified squamous epithelium, typically exhibiting high species and site specificity.
• PV infections are rarely reported in Felidae, making their prevalence and characteristics in this family poorly understood.

Purpose of the Study:

• To identify and characterize papillomaviruses in various feline species.
• To investigate the clinical and histological features of PV-induced lesions in cats.
• To determine the antigenic relatedness and genetic variability of feline PVs.

Main Methods:

• Immunohistochemical screening using monoclonal antibodies against bovine papillomavirus L1 gene product to detect PV capsid antigens.
• Histological examination of epidermal hyperplasia and proliferative lesions.
• Restriction endonuclease analysis of viral genomic DNA from recovered viral isolates.

Main Results:

• Productive PV infections were identified in six cat species, manifesting as proliferative skin or mucous membrane lesions.
• Monoclonal antibodies revealed conserved but differentially expressed capsid epitopes among cutaneous and oral PVs, suggesting distinct viral entities.
• Lesions were locally extensive and multiple, histologically resembling benign tumors seen in immunosuppressed humans.
• Genomic DNA analysis indicated variability among three recovered viral genomes.
• At least eight distinct feline PVs were tentatively identified, infecting either the oral cavity or skin.

Conclusions:

• This study expands the known diversity of papillomaviruses by identifying at least eight novel feline PVs across six species.
• Feline PVs exhibit species and site specificity, similar to PVs in other mammals.
• The findings suggest that feline PVs can induce proliferative lesions with histological similarities to benign tumors in immunosuppressed humans.