Papillomaviridae Flashcards
(26 cards)
What is the morphology of a Papillomavirus?
Genome?
non-enveloped, spherical, icosahedral
Genome = single circular ds DNA
T/F. A papilloma is a benign neoplasm.
True
With which cells is Papillomavirus replication linked to?
Cells in the stratified squamous epithelium of skin and some mucous membranes
In benign warts, does the viral genome of Papillomavirus integrate with the host cell DNA, or remain as an episome? Malignant?
Benign: episome
Malignant: viral DNA integrates into the host DNA
When a papillomavirus becomes malignant, why are E2, E6, E7 important?
- distrupts E2 which is an early viral repressor genes
- E6 and E7 are viral oncogenes and remain intact
- E6 prevents p53 from inducing apoptosis of damaged cells
- E7 binds to Rb and prevents it from stopping growth of damaged cells
Which bovine papilloma viruses cause Fibropapillomas?
BVP 1, 2, 5
Describe the appearance of a fibropapilloma
fibrous core covered with stratified squamous epithelium, outer layers hyperkeratinized
lesions vary from small nodules to cauliflower growths –> grayish black, rough, spiny
Where are some common locations, on cattle, for fibropapillomas?
Udder, teat, head, neck, shoulder
Young bulls: penis tip (makes them not valuable as a stud)
Which BPV causes cutaneous papillomas?
BPV3
How is a cutaneous papilloma different from a fibropapilloma?
No fibrous core: flat with broad base
What happens when a cow eats a bracken fern?
invasive carcinoma of the alimentary tract
bracken ferns contain carcinogens, mutagens, immunosuppressive chemicals
Which BPV can cause transient papillomas in the alimentary tract?
BPV 4
When a cow with BPV 1 or 2 eats a bracken fern…
enzootic hematuria
hematuria and/or bladder cancer!
What type of vaccine can you use to prevent BPV?
wart vaccine
Where do dogs typically get papillomas?
oral cavity!
starts on lips, spreads to buccal mucosa, tongue, palate, pharynx
T/F. Often canine oral papillomas may extend below the epiglottis or into the esophagus.
False
T/F. Canine oral papillomas regress spontaneously.
True
What does koliocytosis mean?
Cytoplasmic vacuolization (seen with canine oral papillomatosis)
T/F. Recovered dogs can be reinfected with canine papillomavirus.
False
Where will you typically see feline papillomas?
Ears
Which papilloma virus causes equine sarcoids?
BVP 1 and 2
T/F. Equine sarcoids is an uncommon neoplasm in horses.
False. Most common neoplasm of horses.
Why might you not surgically remove equine sarcoids?
They come right back
What are the horse breeds most susceptible to equine sarcoids? Most resistant?
Susceptible: Arabian, Appaloosa, American Quarter horse
Less susceptible: Standardbred, Thoroughbred
