HIV

Question 1

Describe the HIV genome.


Answer 1

It is diploid, with two RNA molecules


Question 2

Which proteins do each of these HIV genes code for: env, gag, pol?


Answer 2

env: gp120 and gp41;
gag: p24 which is the virion core;
pol: reverse transcriptase, aspartate protease, integrase


Question 3

A patient presents with low-grade fever and fatigue for weeks, with risk for HIV. How does this bug integrate its genome into host DNA?


Answer 3

Reverse transcriptase converts HIV viral RNA to double-stranded DNA, which is then integrated into the host DNA


Question 4

You prescribe a patient an inhibitor that prevents HIV from binding to T cells. What three proteins should it target?


Answer 4

CXCR4, CCR5, and CD4


Question 5

You are trying to develop a drug that targets the HIV envelope proteins. How are these proteins formed?


Answer 5

env gene encodes a gp160 precursor that is cleaved into gp120 and gp4, which are acquired through budding from the host cell plasma membrane


Question 6

You are trying to develop a drug that targets the HIV envelope proteins. What is the function of these two proteins?


Answer 6

gp120 is the docking protein that helps HIV attach to CD4+ T cell
gp41 is a transmembrane glycoprotein that facilitates HIV fusion/entry


Question 7

In early infection, the virus binds CCR5 on ____, while in late infection, the virus binds CXCR4 on ____.


Answer 7

Macrophages; T cells

Question 8

During what phase of HIV infection does the CD4+ cell count drop most steeply? What else happens in this phase?


Answer 8

Acute phase (first 1–2 months); wide dissemination of virus, seeding of lymphoid organs


Question 9

A man tests positive for HIV. How would you describe to him the four stages and associated symptoms of this disease?


Answer 9

Flu-like, acute HIV—Feeling fine, clinical latency—Falling count, constitutional—Final crisis, opportunistic infections


Question 10

Where does the HIV virus replicate during the latent phase?


Answer 10

In the lymph nodes

Question 11

Envelope acquired via 1)

Answer 11

1) budding from host cell

Question 12

codes for the three enzymes: protease, RT and the integrase

Answer 12

pol

Question 13

encodes for the virion core

Answer 13

Gag

Question 14

encodes for the 160 glycoprotien envelope protein that is cleaved to GP120 and GP41

Answer 14

ENV

Question 15

HIV transmission in males 1)

females 2)

Answer 15

1) predominantly male to male sex contact

2) heterosexual

Question 16

HIV types of transmission:

3 ways

Answer 16

Sexual transmission
Bloodborne transmission
Maternal – Fetal/Neonatal transmission

Question 17

HIV infection overview:

Primary infection takes place, then establishment of infection in 1)

Answer 17

1) gut associated lymphoid tissue (GALT)

2)

Question 18

HIV infection overview:

chronic persistent infection of HIV where?

Answer 18

in the lymph nodes; this is why there is latent stage;

Question 19

Stages of HIV:

1-4

Answer 19

Acute infection:
Latent stage
Falling Count (opportunistic diseases)
Death

Question 20

Stages of HIV:

Acute stage: what causes the symptoms?

Answer 20

The VIREMIA of HIV peaks from three to six weeks AND the CD4+ is very low; then the viremia decreases and the latent stage kicks in;

Question 21

Stages of HIV:

During latent stage, there are no symptoms; why?

Answer 21

Viremia–:> constant RNA copies;

CD4+ –> pretty constant

Question 22

Stages of HIV: Falling count

what and why are there symptoms?

Answer 22

Constitutional symptoms and opportunistic diseases;
After the latent stage, Viremia INC exponentially;
CD4+–> dec rapidly;

Question 23

Stages of HIV: AIDS

part of the falling count phase where the CD4+ count is 1)

Answer 23

less than 200

Question 24

HIV pathogenesis:
HIV crosses the barrier and enters the 1);
HIV first interacts with dendritic cells, then infects the two potential target cells: 2); they are activated and then disseminated from the lamina propria to 3)

Answer 24

1) lamina propria
2) resting CD4+ T-cells or macrophages
3) lymphoid tissue

Question 25

Generation of latency

1) = reservoir

Answer 25

1) Latently infected, resting CD4+ cells

Question 26

Immune Effector Mechanisms:
Humoral response:
Anti-HIV Abs within 1) of primary infection with majority Abs against 2)

Answer 26

1) 3-6 weeks

2) gp41, gp120

Question 27

Immune Effector Mechanisms:
Humoral response:
Antibodies against gp41 and gp120; these antibodies depend on 1); can also carry out 2)

Answer 27

1) N-linked glycosylation;

2) antibody dependent cellular toxicity (ADCC)

Question 28

Immune Effector Mechanisms:
Cell-mediated response:
1-3)

Answer 28

CD4 T cells

CD8 cytotoxic T cells

NK cells

Question 29

HIV serology:

1) corresponds to those times when the virus is avtively replicating; therefore it is increased during 2)

Answer 29

1) P24 antigen

2) acute phase when you see all the symptoms (6wks) AND symptomatic phase after latent is over

Question 30

1) are produced once p24 antigen starts to decrease at about 6 weeks;

Answer 30

1) AntiEnv (envelope) antibodies and anti-p24 antibodies

Question 31

When HIV patient dies, desc. serology

Answer 31

HIGH p24 antigen;

LOW anti p24 antibody

Question 32

Acute HIV Syndrome: 1) after primary infection

Answer 32

1) 3-6 weeks

Question 33

Acute HIV Syndrome:

dermatologic hallmark

Answer 33

white spots on tongue;

Question 34

Acute HIV Syndrome: general s/s

Answer 34

Persistent fever, night sweats;

LYMPHDENOPATHY

Question 35

Acute HIV Syndrome:

Neurologic

Answer 35

Meningitis, encephalitis, peripheral neuropathy, myelopathy

Question 36

Acute HIV Syndrome: coincides w/

Answer 36

INC. viremia and dec. CD4+; goes away when latent stage starts

Question 37

AIDS

CD4+ T cell count

Answer 37

Pneumonocystis pneumonia
tuberculosis
fungal infections

Question 38

AIDS

Viruses cause Gastrointestinal issues:

Answer 38

Candidiasis
CMV,
HSV
Cryptospordia

Question 39

AIDS

Kidney and Genitourinary infection:

Answer 39

Candidiasis, sexually transmitted infections

Question 40

AIDS:Neurologic

Answer 40

Toxoplasmosis, Crytptococcosis, CMV, syphillis, amebiasis

Question 41

Toxoplasmosis by Toxoplasma gondii

Answer 41

AIDS:Neurologic