Detection of six novel papillomavirus sequences within canine pigmented plaques

Abstract

In dogs, papillomaviruses are thought to cause oral and cutaneous papillomas and pigmented plaques. Eight canine papillomaviruses have been fully sequenced to date. Four of these canine papillomaviruses, including Canis familiaris papillomavirus (CPV)-3, CPV-4, CPV-5, and CPV-8, were amplified from pigmented plaques. Given this recent identification of several different canine papillomaviruses within pigmented plaques, it is likely that there are additional papillomavirus sequences that have not been previously identified. The aim of this study was to detect papillomavirus DNA sequences from pigmented plaques and identify potentially novel PV sequences through nucleotide sequence analysis. Polymerase chain reaction was used to amplify DNA sequences of the papillomavirus L1 gene from 27 pigmented plaques. Identification of novel papillomavirus sequences was based upon less than 90% shared DNA homology to any known papillomavirus. Ten different papillomaviruses were detected within the pigmented plaques, including 6 novel PV sequences. CPV-4 was detected within 41% (11/27) of the pigmented plaques, while CPV-5 was identified within 2 pigmented plaques and CPV-3 within a single pigmented plaque. A previously identified novel papillomavirus sequence was identified within 2 pigmented plaques in this study. The remaining 11 pigmented plaques contained 6 papillomavirus DNA sequences that have not been previously reported. These novel PV sequences were most similar to papillomaviruses that have been detected within canine pigmented plaques.

Recent advances in preclinical model systems for papillomaviruses

“…The evolutionary origins of this sequence and its potential function in the viral life cycle remain unknown (Bravo & Felez-Sanchez, 2015). More recent studies have identified several new canine PV types in pigmented plaques, and others that cause malignant lesions between the digits of dog paws (Luff, Rowland et al, 2016; Luff, Affolter et al, 2012; Lange, Tobler et al, 2009; Lange & Favrot, 2011). Again, with the addition of new canine PV types recently discovered, the canine model continues to have value as a model to study multiple PV infections with different tissue tropisms that could infect an individual.…”

Generalized papillomatosis in three horses associated with a novel equine papillomavirus (EcPV8)

“…Genomic DNA was extracted as described previously from fresh frozen tissue (cases 1 and 2) and from microtome sections (5 μm) of paraffin blocks (case 3) . PCR was performed using the degenerate consensus primer set FAP59 (5′ TAACWGTIGGICAYCCWTATT 3′) and FAP64 (5′ CCWATATCWVHCATITCICCATC 3′), and as described previously . After an activation step at 95°C (10 min), there were 40 cycles of denaturation at 95°C (30 s), annealing at 52°C (1 min) and elongation at 72°C (1 min).…”

Dermatopathology – the link between ancillary techniques and clinical lesions

“…Moreover, many infectious pathogens, in particular viruses, are too small to appreciate in routine histopathology. Immunohistochemistry has proven to be very helpful in identifying such pathogens within affected tissues …”

“…There are innumerous examples of the use of antibodies to immunophenotype neoplastic processes, including leukocytic tumours (Figure ), cutaneous glomus tumours and amelanotic melanomas . As intranuclear inclusion bodies are not always evident on H&E, identification of papilloma virus typically is dependent on using the cross‐reactive anti‐bovine papilloma virus (BPV)‐2 antibody . With acute and subacute distemper, canine distemper virus can be identified within keratinocytes of haired skin, footpads and nasal mucosa .…”