Papilloma and Polyoma Flashcards
Papillomavirus structure
dsDNA (Circular)
Nonenveloped
icosahedral capsid
Papillomavirus capsid proteins
L1 + L2
L1 = 80% of virion
L2 = Minor, makes up the rest
There are _____ types of Papillomavirus
100 types
*grouped into 16 groups (A-P)
Papillomavirus strains are classified as _____ or _____
high or low risk
Cervical cancer is consistent with HPV in _____% of cases
75%
Papillomavirus replication occurs in the _____ and assembly occurs in the ______
nucleus, nucleus
HPV replicates in ______ cells
differentiated skin cells
_____ genes stimulate HPV division and growth
Early genes
Based on TISSUE tropism, HPV’s are classified into _____ or ______
cutaneous or mucosal
Cutaneous HPV caused by strains…
1, 2, 3, 4
Cutaneous HPV incubation time
3-4 months
Mucosal HPV known to cause…
Single oral papillomas
Laryngeal papillomas
Most common benign epithelial tumors of the oral cavity are…
Single Oral Papillomas (Mucosal HPV)
Single oral papillomas features (2)
occur at any age
rarely recur
Laryngeal papillomas are associated with strains ______ and ____
6 + 11
Which mucosal papillomas are likelier to recur?
Laryngeal papillomas
A-G warts are caused by
condylomata acuminata
90% of AGW’s are associated with HPV___ and ____
6+11
HPV strains associated with infection of the female genital tract:
16, 18, 31, 45
85% of cervical carcinoma contains _______
integrated DNA from HPV
Explain oncogenesis in terms of cervical dysplasia and HPV
E6 +E7 are oncogenic, and normally inhibited by E1+E2
E2 is broken to promote DNA integration
6 + 7 are free to bind p53 + RB genes and INHIBIT them
Cells of the ________________ are invaded by HPV
basal layer of epidermis
HPV infections can result in two outcomes - what are they?
Latent or Lytic
Latent HPV phase can have ______ and last for ______
no Sx
Last from Months to Years
After HPV latency, what begins?
Production of :
- DNA
- Capsid
- Particles
Expression of structural proteins and vegetative DNA synthesis is limited to
terminally differentiated epidermal cells
Morphologic changes of host cells from HPV infection is called ______
Koilocytosis
HPV viremia lasts how long?
HPV does NOT cause viremia!!
HPV proteins for virus assembly and release
L1, L2, E4
HPV proteins for cell proliferation and replication?
E1 - E7 (*but not E3)
Koilocyte appearance
Multinucleated,
Big, hyperchromatic nucleus with irregular outlines
Perinuclear halo
HPV transmitted on _____
fomites
______ may promote HPV transmission
asymptomatic shedding
Lab tests for HPV can detect ___, ___, or ____
virus Nucleic Acid
Viral Antigens
Koiloctyotic cells
HPV control
- Podophyllin resin, podofilox lotion
- Aldara cream (= immune response modifier, stimulate cytokines and interferon)
- VACCINE
HPV vaccines
Gardasil and Cervarix
Gardasil contains recombinant ____________
VLP’s of 6, 11, 16, 18
Guardasil protects against ____ strains of HPV, which cause 70% of Cervical neoplasias worldwide
16 + 18
Gardasil mechanism
Triggers antibody response that prevents infection from the included types
Gardasil dosing schedule
given in 3 doses
0, 2, 6 months
Polyomaviruses (viruses)
BK + JC
(SV40 [simian] and murine)
Polyomaviruses differences from papillomaviruses
smaller and less complex
replicate in:
- Resp
- urinary
- CNS (JC only)
Polyomaviruses are activated in _______ patients
immunocompromised
(also pregnant patients, but no transmission to the fetus)
Two infections caused by BK virus:
- Ureteral stenosis (renal transplant pts)
- Hemorrhagic cystits (bone marrow transplant pts)
Main JC virus infection
Progressive Multifocal Leukoencephalopathy (PML)
*occurs in IC patients (e.g. AIDS)
JC virus infects _____ cells, which results in ….
Oligodendrocytes
multifocal demyelination of CNS
PML prognosis
1-4 months
Polyomaviruses are limited to _______ and _______
specific hosts + cell types
JC+BK enter the ________ and infect ________
Then enter the _______ with minimal effect
respiratory tract
lymphocytes
kidney
BK virus establishes _______ in kidney
latent infection
JC cirus establishes infection where?
kidneys, B cells, monocyte-lineage cells
After multiplication in the kidney, JC/BK cause ____________ , which either results in permanent latent kidney infection (in non-IC) or reactivation and progression (in IC pts).
causes transient secondary viremia
BK more likely to cause _____ infections,
JC may cause _____ infection
BK –> UTI
JC –> CNS
Polyomaviruses control/treatment
None