Lecture 6: Papilloma Virus Flashcards
Most common STI in the world
HPV
HPV
-genome
-envelope
-transmission
Human papilloma virus
-dsDNA, circular
-no envelope
-direct contact (sexual, fomites, birth canal)
many infections asymptomatic, but virus still shed
anal cervical cancers the most
HPV have tropism for
Squamous epithelial cells
-virus enters through small cutes/infects basal layers or mucous membrane- replicates locally
-infectious virions are only produced in the outermost epithelial cells
Pathogenesis for HPV?
Binding to the BM triggers infection of adjacent basal cells- ensures infection of the only cells that divide
Cell proliferation of HPV occurs where?
When do Koliocytes appear?
Basal cells
Cell proliferation= dividing cells (entry and uncoating occur)
Koliocytes appear during genome replication and virion maturation
Characteristic CPE of HPV are
Koliocytes (clear holes surrounding shrunken nuclei)
Pathognomic for HPV infection
Koliocytes
What are the Low-risk types for HPV ?
Types 6 and 11
-condylomata acuminata
(Genital warts or benign lesions)
-all= types 6, 11, 42, 43, 45
What are the high-risk types for HPV
High-risk types 16, 18, 31, and 33 (everything else)
=cervical cancer
= high risk for anogenital, oral, and oropharyngeal squamous cell carcinoma
Genital warts are characterized as what type of HPV
Types 6 and 11
Hand warts are characterized as what type of HPV
Types 2 and 4
Plantar warts are characterized as what type of HPV
HPV 1
Flat (face) warts are characterized as what type of HPV
HPV 3, 10
Oral warts are characterized as what type of HPV
HPV 6, and 11. Sometimes HPV 16
= oral condylomata
=oral warts in/around the mouth
-Filiform wart
Multifocal epithelial hyperplasia
-manifestations
-type
Heck’s disease “what the heck”
-cobblestone appearance
-HPV 13, and 32 (high-risk)
Laryngeal warts
-what is it
-types
Recurrent respiratory papillomatosis (laryngeal papillomatosis)
-rare
-papillomas restrict the airways
mother with genital warts can give child this
-HPV 6, and 11
Conjunctival papilloma
-HPV 6, and 11 and sometimes 16
-generally benign
Oropharyngeal cancer
-type
-manifestations
-oropharyngeal cancer squamous cell carcinoma
HPV 16
Generally occurs at the base of the tongue and tonsil, but also the larynx
How does HPV cause cancer?
What are the 3 proteins that are considered oncogenes?
-HPV DNA integrates into cellular DNA causing loss of normal cell cycle
-E5: stabilizes epidermal growth factor receptor
-E6 & E7: prevent function of tumor suppressor proteins (high risk HPV’s)
Treating HPV
Most warts will regress spontaneously over time (treatment does not eliminate infection and warts can recur)
-chemical solutions, (salicylate acid)
-physical methods, (laser, cryotherapy)
-immune stimulation, (IFN)
-antivirals (cidofovir = for immunocompromised patients)
-vaccine ( Gardasil 9)
Preventing HPV
Gardasil 9
-Types 6, 11,
-Types 16, 18, 31, 35, 45, 52, 58
What HPV types cause skin warts
HPV 1,2,4
Gold standard for diagnosing HPV
-PCR
you can also diagnose with a pap smear
How long does it take for warts to become present in HPV ?
3-4 months
-infected cells are stimulated to divide, causing a thickening of the skin.
