HIV/AIDS I Flashcards
HIV is a group ___ virus; what is the shape of the virus?
HIV is a group VI virus; enveloped, spherical
HIV has more ____ than simple retroviruses that code for ____
HIV has more ORFs than simple retroviruses that code for small proteins
describe circulating recombinant form
different subtypes can combine genetic material to form hybrid virus
____ is the glycoprotein on the HIV envelope that is used for attachment
gp120 is the glycoprotein on the HIV envelope that is used for attachment
____ is the glycoprotein on the HIV envelope that is used for fusion of the viral envelope to the host cell
gp41 is the glycoprotein on the HIV envelope that is used for fusion of the viral envelope to the host cell
____ forms the outer layer of the HIV virion core and detection in the blood indicates infection
p24 forms the outer layer of the HIV virion core and detection in the blood indicates infection
list the genes that simple retroviruses encode
- Gag = group-specific antigen (core and capsid proteins)
- Pol = polymerase (reverse transcriptoase, protease and integrase)
- Env = envelope (glycoproteins)
- Pro = protease
- Int = integrase
____ is the gene that is responsible for the progression of a patient from acute HIV to AIDS
nef is the gene that is responsible for the progression of a patient from acute HIV to AIDS
describe the transmission of HIV
____ reduces heterosexual transmission
male circumcision reduces heterosexual transmission
HIV protease ____ long chains of ____ into ____
HIV protease cuts long chains of HIV proteins into smaller individual proteins
in the HIV virus life cycle, maturation occurs when _____
in the HIV virus life cycle, maturation occurs when HIV protease cuts long chains of HIV proteins
HIV binds to a ___ and ___ on the surface of a ____
HIV binds to a CD4 receptor and co-receptor on the surface of a CD4+ T lymphocyte
____ is the co-receptor found on macrophages, dendritic cells and CD4 T cells
CCR5 is the co-receptor found on macrophages, dendritic cells and CD4 T cells
___ is a co-receptor found only on CD4 T cells
CXCR4 is a co-receptor found only on CD4 T cells
naive HIV infections use the ____ receptor which is also present on _____
naive HIV infections use the CCR5 receptor which is also present on macrophages
____ converts ssRNA to dsDNA with random errors due to ____
reverse transcriptase converts ssRNA to dsDNA with random errors due to poor proofreading abilities
integrated HIV DNA is called ____ which may remain ____ for several years, producing ____
integrated HIV DNA is called provirus which may remain inactive for several years, producing few/no new copies of HIV
____ helps insert the HIV DNA within the host cell’s own DNA
HIV integrase helps insert the HIV DNA within the host cell’s own DNA
____ cells accumulate the virus particles on their surface and carry the virus to ___ resulting in efficient infection of CD4 T cells
dendritic cells accumulate the virus particles on their surface and carry the virus to lymph nodes resulting in efficient infection of CD4 T cells
there is ____ in gp120 which allows for evasion of antibody detection
there is antigenic drift in gp120 which allows for evasion of antibody detection
what causes HIV to evade antibody detection?
direct cell-to-cell spread and syncytia formation
how does HIV shield itself from the immune system and current antiretroviral drugs?
viral latency in resting T-cells and APCs
multinucleated giant cells in the CNS appear to the result of ____ of HIV-infected ___ and ____
multinucleated giant cells in the CNS appear to the result of syncytial fusion of HIV-infected macrophages and microglia
describe the course of HIV progression and AIDS
when does HIV testing in pregnant women occur?
first trimester and third trimester if there is a high risk
what test is used for HIV detection 11-12 days after infection?
HIV RNA test = measures level of HIV nucleic acid/RNA
what test is used for HIV detection 14-15 days after infection?
p24 antigen test = measures level of HIV p24 core protein
what test is used for HIV detection 3-8 weeks after infection?
ELISA for HIV antibodies = detects presence of HIV antibody; positive test confirmed by Western blot
a positive Western blot test requires ____
a positive Western blot test requires 2 bands out of 3 to be positive:
p24
gp41
gp120/160
in the diagnosis of HIV:
step 1 is ____
step 2 is ____
step 3 is ____
in the diagnosis of HIV:
step 1 is Ag/Ab immunoassay (ELISA)
step 2 is Ab-differentiation immunoassay (Western blot)
step 3 is NAT
____ is suggestive of severity of infection, progression of disease and monitoring therapy
viral load is suggestive of severity of infection, progression of disease and monitoring therapy
which 2 specific tests should be done during the initial HIV care visit?
- syphilis serology
- NAATs for gonorrhea and chlamydia
____ is used in treatment for HIV; which 2 criteria makes a treatment successful?
highly active antiretroviral therapy (HAART) is used in treatment for HIV
- successful tx:
- gradual recovery of CD4 T cell numbers
- reduction in viral load