HPV Vaccines Flashcards
HPV classification
Dermal
Mucosal
- low risk
- high risk
5 evolutionary groups of HPV
- Alpha
- Beta
- Gamma
- Nu
- Mu
Common low-risk HPV
6,11
- genital and oral warts
Common high-risk HPV
16,18
Average time to clear HPV infection
8-12 months
Risk factors for incident HPV infection
- lack of condom use
- new sex partner
- no. of previous sex partners
HPV genome organisation
- double stranded
- closed circular
- DNA
- 8000 bps
Family of HPV
Papillomaviridae
Genus of HPV
Alphapapillomavirus
How the virus penetrates the cervix
- skin-skin contact
- point of entry = abrasion
How does the virus disable suppressors
- expression of viral protein E6+E7
- inactivate anti-oncogenic p53 and pRB
Role of p53
- a transcription factor which controls DNA repair and cellular response to injury
- initiates apoptosis in damaged cells
Role of pRB
- halts DNA replication during G1 phase of cell cycle to allow repair of damaged DNA
Where does HPV replicate?
in stratified squamous epithelium
How does HPV evade the IS?
- not cytolytic and so no IS activation
- interferes with interferon responses
- fewer inflam cytokines so no induction of adaptive immunity
- downreg HLA class 1
- replicates in avascular area (no access for immune cells)
Diagnostic tests for HPV
- Digene hybrid capture
- HPV Genotyping by linear array (research only)
Describe Virus-like particles
- have same L1 protein coat but no genetic material
- enables strong protective immune response
Key findings in HPV
- protection for at least 5 years
- both vaccine provide cross protection
- no therapeutic value
For whom is the HPV vaccine recommended?
- females 13-26
- males 13-26
