Development of a PCR Assay to detect Papillomavirus Infection in the Snow Leopard

We used the sequence of the snow leopard papillomavirus UuPV1 to develop a PCR strategy to amplify viral DNA from samples obtained from captive animals. We designed primer pairs that flank the E6 and E7 viral oncogenes and amplify two DNA fragments encompassing these genes. We detected viral DNA for E6 and E7 in genomic DNA isolated from saliva, but not in paired blood samples from snow leopards. We verified the identity of these PCR products by restriction digest and DNA sequencing. The sequences of the PCR products were 100% identical to the published UuPV1 genome sequence.We developed a PCR assay to detect papillomavirus in snow leopards and amplified viral DNA encompassing the E6 and E7 oncogenes specifically in the saliva of animals. This assay could be utilized for the molecular investigation of papillomavirus in snow leopards using saliva, thereby allowing the detection of the virus in the anatomical site where oral papillomatous lesions develop during later stages of infection and disease development.Papillomaviruses (PVs) are a group of small, non-encapsulated epitheliotropic DNA viruses. PVs infect basal keratinocytes and cause benign proliferative lesions, termed papillomas, on the surface of cutaneous and mucosal tissues [1]. A subset of PVs are associated with the development of epithelial malignancies, such as cervical carcinomas, oral squamous cell carcinomas (OSCCs) and head and neck squamous cell carcinomas (HNSCCs) in humans [2,3]. The genomes of PVs are circular and double-stranded and contain up to 8 viral genes that are classified as early (E) or late (L) based on their temporal pattern of expression. Early genes encode regulatory proteins that function in viral replication (E1 and E2), viral shedding (E4), or transformation (E5, E6 and E7) [4], whereas late genes (L1 and L2) encode viral capsid proteins (Figure 1a) [1,5]. PVs are strictly species-specific and have been identified in a wide variety of vertebrates, including mammals, birds and re