HIV, AIDS: Immune Function 08 22 14 Flashcards
why are blood exposures higher risk than sexual exposures for getting HIV?
semen and vaginal fluid don’t have as much HIV particles in them as blood and in sex, presumably no blood
also, blood (directly given) bypasses the epithelial layer
what is the immunologic basis for differential risk for acquiring HIV associated with various sexual behaviors?
different tissues-different cells
more target cells for HIV to invade in the GI/anus (more WBCs)
men with uncircumcised or circcumcised penises have higher chance of getting HIV?
uncircumcised as higher risk
window period for HIV definition
when routine HIV antibody tests are negative but HIV virus can be detected in blood
when do you see signs and symptoms for HIV?
they start usually 1-4 weeks after exposure
when is risk of transmission of HIV highest for untreated HIV?
in acute infection (beginning) and at end (AIDS)
what causes drop in viral load of HIV after acute infection?
CD8+ T cell response
when does antibody against HIV become detectable?
a month later
what is the problem with just testing for HIV with viral load?
cross contamination in lab possible-false positive
why is humoral response blunted for HIV?
surface glycosylation-changes on HIV surface prevent neutralizing Ig binding but not receptor binding
immune reconstitution inflammatory syndrome (IRIS)
paradoxical deterioration in clinical status after starting antiretroviral therapy due to recovery of the immune response to latent or subclinical infections
what can we look at to determine HIV prognosis?
CD4 T cell count
immune activation markers (CD4 T cell depltion results in damage of gut mucosa, increased gut permeability, leading to bacteria moving from gut lumen to submucosa and increased plasma LPS levels)
