Lecture 16 - Human retroviruses

Question 1

Which countries/areas of the world have the highest prevalence of HIV-1 infections

Answer 1

Africa and Asia; 28% Africa

Question 2

What 5 things make up the retrovirus structure

Answer 2

capsid, RNA, envelope glycoproteins, matrix proteins, reverse transcriptase

Question 3

What are the 2 envelope glycoproteins of the retrovirus structure?

Answer 3

gp41 and gp120

Question 4

What is a provirus?

Answer 4

genetic material of a virus

Question 5

What are the 4 essential proteins?

Answer 5

gag, pro, pol, env

Question 6

What are the 6 steps in the retrovirus replication cycle?

Answer 6

penetration, reverse transcriptase, integration to host DNA, transcription/translation, assembly, budding, release

Question 7

What is the host receptor that HIV attaches to?

Answer 7

CD4

Question 8

Which type of cells does HIV 99% replicate in?

Answer 8

uninfected CD4 lymphocytes

Question 9

Which type of cells does HIV <1% replicate in?

Answer 9

macrophages and infected resting CD4 lymphocytes

Question 10

Are HIV viruses lysogenic or lytic viruses? Why?

Answer 10

lysogenic, they can be latent

Question 11

What is HTLV viruses?

Answer 11

human t-cell leukemia-lymphoma virus

Question 12

Which HIV causes AIDS in Africa and has less infections?

Answer 12

HIV-2

Question 13

Which HIV is the main causative agent of AIDS?

Answer 13

HIV-1

Question 14

How many clinical categories of HIV infections are there?

Answer 14

3

Question 15

Which clinical category of HIV infection includes asymptomatic patients as well as mildly symptomatic?

Answer 15

category A

Question 16

Which clinical category of HIV infections includes severely infected persons and can lead to cancer?

Answer 16

category C

Question 17

What happens to a person infected with HIV for 2 years?

Answer 17

acute infection

Question 18

What happens to a person infected with HIV for 4 years?

Answer 18

asymptomatic infection

Question 19

Around what year of HIV infection will the infected individual experience Candidiasis (yeast infection)?

Answer 19

7 years

Question 20

What happens to a person infected with HIV for 12-16 years?

Answer 20

PCP, dementia, wasting and death

Question 21

What happens to the brain of a patient infected with AIDS?

Answer 21

destruction of brain tissue

Question 22

What are the 4 possible sites if inhibition of HIV replication?

Answer 22

fusion, reverse transcriptase, integrase, protease

Question 23

How was HIV infection identified as a viral infection?

Answer 23

blood bank filtered blood into the filter to give to hemophiliac patients who got infected with HIV = virus passed through the filter

Question 24

By 2010, how many people in the US were infected with AIDS and how many people died?

Answer 24

1 MIL infected; 500K died

Question 25

How many people worldwide are affected with AIDS and how many people died?

Answer 25

33 MIL infected ; 1.6-2.6 died

Question 26

What percentage of the US population is infected with AIDS?

Answer 26

0.5-1.2%

Question 27

What shape is the HIV virus?

Answer 27

icosahedral

Question 28

What gene is the proteins gp120 and gp 41 expressed on?

Answer 28

same gene but cleaved by protease

Question 29

What protein does gag gene encode for?

Answer 29

p17 protein in the matrix and capsid proteins too

Question 30

What proteins does pol gene encode for?

Answer 30

polymerase and reverse transcriptase

Question 31

How long does the provirus within the human chromosome?

Answer 31

years = latency

Question 32

How long does it take for HIV to replicate?

Answer 32

2.6 days

Question 33

Which HIV type causes 95% of AIDS infections?

Answer 33

95%

Question 34

How long does it take for a person to develop AIDS from an HIV infection?

Answer 34

10-16 years

Question 35

How many drugs must one use for later stages of HIV?

Answer 35

cocktail of 3

Question 36

Why are first antivirals only effective for a short time during initial stages of infection?

Answer 36

due to mutations

Question 37

Why are glycoproteins not used as a target?

Answer 37

hard to target

Question 38

What makes reverse transcriptase difficult to target?

Answer 38

has many errors or mutations

Question 39

What are the main sites of inhibition of HIV replication?

Answer 39

protease and reverse transcriptase