HIV

Question 1

What is the function of gp120 protein in HIV?

Answer 1

An envelope protein that adheres the virus to its target Th cell/macrophage
(target must have the receptor CD4; as well as a coreceptor CCR5 or CXCR4)

Question 2

What is the viral transmembrane envelope protein involved in FUSION of the viral and host membranes?

Answer 2

gp41

Question 3

The 3 big structural genes of HIV’s genome are?

Answer 3

env gene (envelope proteins)
gag gene (group Ag)
pol gene (polymerases)

Question 4

______ is the primary coreceptor in HIV infections, and _______ is a coreceptor used later in infections.

Answer 4

CCR5

CXCR4

Question 5

Drugs used in HAART primarily target products of what HIV gene?

Answer 5

pol gene

this encodes for reverse trascriptase, aspartate protease, and integrase

Question 6

The product of what HIV gene will be detected in ELISA screening exams?

Answer 6

gag gene

encodes for capsid protein (p24)

Question 7

Another name for reverse transcriptase is?

Answer 7

RNA-dependent DNA polymerase

it synthesizes DNA from HIV’s RNA genome

Question 8

What regulatory gene is required for HIV to progress to AIDS?

Answer 8

Nef gene

if the virus is Nef-deficient, the infected person will be HIV+ but asymptomatic

Question 9

Describe the process of HIV diagnosis

Answer 9

Presumptive screening: ELISA, looking for p24

after 2 positive ELISAs=confirmed with Western blot

Question 10

What test is done to determine the viral load in the patient?

Answer 10

PCR; great for checking how well the drugs are working

Question 11

What cytokine causes wasting in AIDS patients?

Answer 11

TNF-a

Question 12

What is the function of the aspartate protease?

Answer 12

the HIV genome makes one big product; the protease cleaves the product into viable proteins/enzymes so the virus can repackage and infect other cells

Question 13

What T cell count defines AIDS?

Answer 13

CD4 count<200