PAPILLOMAVIRIDAE Flashcards
Describe the genome of Papillomaviridae and Polyomaviridae.
Circular double-stranded DNA
Papillomaviruses can cause visible (proliferative, usually exophytic focus of epithelial thickening) on the ____ and ____ membranes.
skin; mucosal
Papillomavirus-induced papillomas causes ?
warts (hyperplastic lesions) —> most common in young animals —> invariable spontaneously RESOLVE
Nonviral papillomas causes?
Benign neoplasms —> older animals —> NOT RESOLVE
Cutaneous (skin) papillomas are most common in what animal?
Cattle
Oral papillomas are seen frequently in what animals?
Young dogs and rabbits
Genital papillomas are common in ?`
Domestic livestock
Diagnostic methods for Papillomaviruses
- Histological observation (cytopathologic features)
- Immunohistochemistry
- PCR
- Next generation sequencing
Papillomavirues can easily be grown in cell cultures. True or False?
False
Vast majority of papillomaviruses only infect _____ and induce _____ papilloma comprised of thickened folded epithelium.
keratinocytes; squamous
This papillomavirus causes proliferation of both keratinocytes and underlying fibroblasts producing fibropapillomas.
Deltapapillomaviruses
Give the virion property of Papillomavirus.
Nonenveloped, spherical, icosahedral symmetry
Replication of Papillomaviruses is linked to growth and differentiation of cells in ?
Stratified squamous epithelium
Give the pathogenesis of Papillomavirus.
- Starts with microtrauma
- Interaction of papillomavirus with basement membrane
- Infection of secondary receptor of basal keratinocyte
- Cell entry
- Transportation to various locations
Most papillomaviruses strongly increase keratinocyte replication. True or False?
False, mildly
Papillomaviruses has an ability to force the infected cell to keep dividing and retain their
nuclei via the expression of ?
Additional E genes
Papillomaviruses cause cell lysis. True or False?
False
In productive replication, cellular changes are observed including ?
Enlarged cells with
shrunken nuclei surrounded by a clear halo (koilocytes)
This prevents the infected cell from leaving the cell cycle; classified as oncoproteins
E proteins
Papillomavirus-induced papillomas and fibropapillomas are recognized more commonly in _____.
cattle
Transmission modes of Papillomavirus in cattle
- Fomites
- Rubbing posts
- Wire fences
- Sexual transmission
Cattle papillomavirus: Infection of epithelial cells results in hyperplasia and hyperkeratinization, usually within ___ weeks of exposure.
6
Cattle papillomavirus: In general, papillomas persist for _____ months before spontaneous regression.
1-6 months
Give the histological features of fibropapillomas.
- Extensively thickened folded epithelium
- Productive papillomavirus replication overlying a typically normal dermis
Give the histological features of fibropapillomas.
- Exophytic or pedunculated
- Small firm nodules to large CAULIFLOWER-LIKE GROWTHS
- Grayish to black in color
- Rough and spiny to the touch
- Proliferation of dermal fibroblasts that form a fibrous core
Papillomavirus in cattle causes benign self-resolving papillomas. True or False?
True
Bovine papillomaviruses have been associated with ?
Neoplasia - BPV-2 associated bladder cancer & BPV-4 associated upper alimentary tract
Give the diagnostic methods for Bovine papillomaviruses.
- Histologic detection of virus-induced cell changes
- Immunohistochemical detection
- Electron microscopic visualization
What are the preventive measurers for Bovine papillomaviruses?
o Inactivated bovine papillomavirus
o Viral capsid proteins produced by recombinant DNA technology prevents
papilloma formation
o But there is currently little justification for routine vaccination to prevent papillomavirus infections of cattle
What are the therapeutic strategies for Bovine papillomaviruses?
o Inoculation with formalin-inactivated, homogenized, autologous wart tissue
o But efficacy has never been properly evaluated
Papillomaviruses of horses: Give the causative agent and clinical signs of cutaneous papillomas in horse.
*** Caused by EcPV-1
o Small, elevated, keratinized lesions
o Common around lips and nose of young horses
o Also occur on ears, eyelids and limbs
o Generally regress within 9 months
o Some elect surgical excision
Papillomaviruses of horses: Give the causative agent and clinical signs of aural plaques in horse.
*** Associated with EcPV-3, 4, 5, 6
o Descrete, raised, smooth or rough-ended pale plaques or nodules on the inner surface of the pinnae of the ear
Papillomaviruses of horses: Give the causative agent and clinical signs of genital papillomas in horse.
*** Caused by EcPV-2
o Singularly or multiple papillomas covering much of the penis (papillomatosis)
Papillomaviruses of horses: Give the causative agent and clinical signs of penile and preputial squamous cell carcinomas in horse.
*** EcPV-2
o Relatively common cancers of horses
Papillomaviruses of horses: Give the causative agent and clinical signs of sarcoids in horse.
*** BPV-1, -2, -13
o Most common skin tumor of horses, mules and donkeys
o Appearances: verrucous (wart-like), fibroblastic, mixed, flat
o Treatments: surgical excision, cryotherapy, hyperthermia, chemotherapy, radiation therapy, antiviral treatments, immunomodulation
Papillomaviruses of Dogs (Canine oral papillomavirus): Give the causative agent and clinical signs of oral papillomas in dogs.
*** CPV-1
* Oral papillomas, cutaneous papillomas, cutaneous pigmented plaques
* Affected dogs are typically young
* Warts usually first develop on the lips, but can spread to the buccal mucosa, tongue, palate, and pharynx
