HIV Flashcards
HIV characteristics
RNA retrovirus
proteins
gp120 (docking)
gp41 (transmembrane)
reverse transcriptase
life cycle
RNA must become DNA
then copy of DNA
sent to nucleus and integrated into host genome via integrate
protease carves large polyprotein into pieces
then assembled and buds
primary HIV target
activated CD4 T cell
also MP’s, microglial cells
thus HIV prefers fighting against an activated immune system (paradox)
plays a role in cancer surveillance
cell-mediated immunity
HIV pathogenesis
gets across mucosal barrier and picked up by dendritic cells and delivered to regional lymph node –> where CD4’s are at!
HIV depletes the CD4 cells in the gut Peyer’s patches –> enteropathy –> microbial translocation –> immune activation –> HIV can then affect new cells
HIV binding
needs to bind
CD4 w/gp120
also co-receptor
gp41 is like a spiral loop that brings HIV closer to the target cell
drug is like a rod (fusion inhibitor) that stops gp41 from springing
2 main coreceptors
CCR5 (R5 viruses use this)
CXCR4 (X4 viruses use this)
there are also dual tropic viruses
HIV diversity w/in the individual
compact genome
RT highly error prone
high replication
the ultimate HIV trick
latent reservoir in memory cells that has HIV genome integrated
antiretrovirals only work on activated virus
clues to HIV presentation?
flat, red rash (not seen in mono)
aseptic meningitis
oral/genital ulcers (not in flu)
massive fatigue
HIV antibody appears when?
after the “window period”
during this time, must look directly for the virus (HIV-RNA: only detect in acute or active infection, or p24Ag)
Chronic symptomatic HIV
fatigue persistent generalized lymphadenopathy dermatologic problems (zoster, simplex, skin/nail) hairy leukoplakia, thrush seborreic dermatitis
