HIV 1 Flashcards
HIV prevalence in Oz?
17 000
95% of HIV are female or male?
male
HIV envelope?
yes
HIV origin?
zoonosis, bush meat consumption
name of HIV envelope proteins?
gp120
gp41
structure of HIV gag and env proteins stable or variable?
high degree of variability
where do you find CD4 receptors?
macrophages
T-lymphocytes
after budding of HIV, what needs to happen?
maturation
why is HIV elusive and hard to cure?
after reverse transcriptase it can integrate into genome as DNA and remain dormant and invisible
what does reverse transcriptase contribute to HIV’s elusiveness to our immune system?
has high error rate thus mutations
HIV-1 membrane fusion sequence?
- gp120 to CD4
- chemokine coreceptor (CCR5, CXCR4)
- coreceptor promotes gp41 fusion to membrane
temporal difference with CCR5 and CXCR4?
CCR5 - early
CXCR4 - late
HIV particles selectively infect with which strains?
R5 strains for CCR5
after initial replication of HIV in resting T-cell what happens?
silencing of HIV expression
how does HIV expression increase after silencing?
T-cell immune activation
Nf-kB contributes to HIV how?
transcription factor made by active T-cells and acts as core enhancer
Cis and Trans acting factors do what to HIV basal transcription?
Cis - integration/chromatin
Trans - T-cell activation (Nf-kB)
which HIV regulatory proteins are essential for HIV replication?
Tat - transactivator of HIV transcription
Rev - regulator of gene expression
Nef, vpu important in Vivo pathogenesis how?
down modulates MHC-1 and CD4 to decrease CTL
what is Tetherin, TRIM5a, APOBEC3G?
humans’ “natural defenses” against HIV
All have been overcome by virus
HIV vpu does 3 biggies:
- degrades CD4
- antagonizes tetherin
- inhibit CD1d expression
what does Vif do?
degrade APOBEC3 (human HIV defense)
what needs to happen in HIV particle maturation?
Gag-pol precursor protein needs to be cleaves into individual proteins
main latent HIV reservoir?
central T-cells
memory T-cells
problem with latent HIV reservoir?
- Treatment can’t touch it
2. comes back if you stop treatment
what regulates HIV transcription?
Tat
how to measure provirus/virion?
sensitive PCR
