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Flashcards in Immunology and AIDS Deck (33)
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1

When Th(CD4+) cells fall below _____ of blood, a diagnosis of AIDS is made.

200/microliter

2

What percentage of people living with AIDS are unaware?

16%

3

OraQuick is a home test for HIV antibody why is it unreliable?

Because it gives a lot of false negatives (1:12)

4

Which strain of HIV has not gone global yet?

HIV-2

5

Describe HIV.

Nontransforming retrovirus that uses reverse transcripase to copy its RNA genome to DNA

6

HIV is a part of what group of viruses?

Lentiviruses

7

What virus is HIV most closely related to?

Simian Immunodeficiency Virus, SIV

8

What is considered risky behavior?

Sexual contact with someone with the disease
Any contact through injured mucous membrane

9

Do circumcised males decrease the spread of HIV?

Yes

10

"Long term survivors" are genetically unique in that they....

Have a homozygous deletion of CCR5
Their T cells can't get infected, but there DC and macrophages can
Found in 10% of Caucasians

11

What are Elite controllers?

HLA-B57 make effective CTL to HIV peptides presented in HLA-B57. Can become infected but did not progress to AIDS

12

After exposure at what time does the antigen peak in the body?

At what time does the antibody peak=?

6 weeks

9 weeks

13

What is a DC-SIGN?

When HIV adheres to a lectin on dendritic cells

14

What viral protein binds CD4+ and then CCR5?

gp120

15

What is gp41?

Glycoprotein associated with gp120. That, when it changes its conformation, exposes a very hydrophobic region that literally melts away the T cell's membrane so the cell and virus fuse

16

What helps the double-stranded DNA copy of HIV insert into the host DNA?

Viral integrates helps it insert into a random break

17

How many genes does HIV encode?

9

18

How often is the entire population of virus replaced?

Everyday.

19

How can syncytium form between two T cells?

gp120/gp41 is made early and inserted into the membrane. That way a infected T cell can infect a healthy T cell without the virus being released

20

HIV persists in memory Tfh cells so as the disease progresses what other cell line is likely to be affected?

B cells

21

Name some opportunistic infections associated with AIDS.

Candida or the mouth, esophagus, and rectum
TB- Most common cause of death
Kaposi sarcoma
Burkitts
Late AIDS dementia- infection of microglia

22

Is a positive ELISA test enough evidence to diagnose someone with HIV?

No because ELISA has a lot of false positives. You would have to follow with a western blot for HIV antibodies

23

What can you do to test what therapies will have the most effectiveness?

PCR

24

What was the first treatment for AIDS introduced in 1987?

AZT

25

name two classes of Reverse transcriptase inhibitors.

1. Nucleosides (NRTI)- Competitve inhibitors & chain terminators
2. Non-Nucleoside (NNRTI)- Bind to hydrophobic pocket on enzymes that changes the conformation and activity of catalytic site.

26

You can use a protease inhibitor for products of what three genes?

gag
pol
env
Which all make proteases

27

What drug binds to gp41 preventing conformational change so it cannot melt the membrane?

Enfuvirtide-Fusion inhibitor

28

What drug acts as a CCR5 antagonist and blocks viral entry?

Maraviroc

29

What drug acts as a integrase inhibitor?

Raltegravir

30

What is the standard antiretroviral therapy (ART)?

Combines two NRTI and a third drug from a different class