Retroviruses (HIV, HTLV) Flashcards Preview

Microbiology Block 1 > Retroviruses (HIV, HTLV) > Flashcards

Flashcards in Retroviruses (HIV, HTLV) Deck (38):
1

what is the biology of HIV?

enveloped with 2 copies of single stranded +RNA

2

what Virus attachment proteins (VAP) found on the envelope of HIV?

GP 120

GP 41

3

what is the major capsid protein found in HIV?

p24

4

what enzymes does HIV have?

integrases

proteases

reverse transcriptase

5

which of the 2 membrane proteins in HIV will define its tropism?

GP 120

6

what cells does HIV target?

CD4+ cells

7

antiviral drugs for HIV will target what protein of the virus?

gp 41

8

HIV protein Gp 120 will bind to what cell and what co-receptor if it's M tropic?

it binds to CD4+ (memory CD4 T cells, Dendritic cells, macrophages)  cells and its co-receptor CCR5

9

HIV protein Gp 120 will bind to what cell and what co-receptor if it's T tropic?

if its T tropic it binds to CD4+ (activated T cells) cells and CXCR4 

10

what will the HIV Gp 41 protein do?

it will fuse the viral envelope with cell plasma membrane

11

what is the first stage of HIV replication?

what symptoms are seen?

1st stage = we will replicate in the macrophages and dendritic cells in the lymph nodes

 (swollen lymph nodes, and high virus, no antibodies)

 

 

12

what is the second stage of HIV replication?

2nd stage = virus lives inside T cells, disseminates throughout body but remains latent, it is in DNA form, low HIV virus, we have high antibodies

 

 

13

what is the 3rd stage of HIV replication?

3rd stage = virus is all over, shifts to CXCR4 in CD4 and attacks our active T cells and strats making many virion particles which will look for GP120 

14

where do we find the largest amount of cases of HIV-1 infection?

sub-saharan africa 

15

where do we find the largest amount of cases of HIV-2 infection?

West africa 

16

who is at risk of being transmitted HIV?

intravenous drug abuser (sharing needles)

sexually active individuals (homosexuals, prostitutes)

newborns of HIV positive mothers

organ transplant patients

17

what cells are most prone to infection by AIDS and what cells are used for latency by the virus?

T cells and macrophages

CD4+ T cells by incorporating DNA into host genome

18

what individuals are most prone to be resistant to HIV infection?

CCR5 receptor deficient individuals 

19

if there is a mutation in the GP 120 protein of HIV, how will this affect its tropism?

its tropism will shift from M-tropic to T-tropic

20

what is HIV's pathogenesis?

1) lytic infection of CD4 T cells (having the virus infect start to infect some macrophages)

2) reduction in CD4 T cell numbers 

21

what happens when you are have the HIV acute illness?

what symptoms are seen?

will see drop in CD4+ cell count 

flu-like symptoms are seen

22

what happens when you have HIV latent infection?

what symptoms are seen?

the virus is in provirus form

test will be positive for HIV antibodies

destruction of CD4 cells will continue

 

no symptoms are seen

23

24

what happens during the symptomatic phase of HIV?

what symptoms will be seen?

CD4+ cell count is less than 500 

increased level of virus

 

weight loss, continual diarrhea, extreme fatigue, oral thrush 

25

what bacteria causes oral thrush seen in HIV symptomatic phase?

candida

26

what happens in full blown AIDS by HIV virus?

what symptoms are seen during this phase?

CD4 is less than 200

antibody test is negative

 

kaposi sarcoma, thrush, severe CMV, dementia

 

27

what are 3 opportunisitc infecions seen in AIDS?

1) Pneumocystis jiroveci Pneumonia (PCP)

2) Candidiasis (oral thrush)

3) cryptococcocis (meningitis)

28

what fungal infection is most defining of AIDS?

PCP

29

what is the most common fungal infection of the CNS?

cryptococcosis

30

what is the most common fungal infection overall?

candidiasis

31

what are 2 of the most common bacterial infections found in AIDS?

1) Mycobacterium avium intracellular complex (MAC) (lung and esophagus infection)

2) Salmonella typhimurium

32

what is the 2 most common viral infections found in AIDS patients?

1) CMV

2) Herpes Simplex Virus 

33

what does CMV lead to in AIDS?

- retinitis

- esophagitis

-  colitis (diarrhea)

cholecystitis

34


How do CMV infections differ in immunocompetent vs. immunosuppressed patients?
 

In immunocompetent patients, an acute CMV infection results in a syndrome resembling acute infectious mononucleosis. 

In the immunosuppressed patient, CMV disease, whether acquired primarily or as a result of reactivation, may be a disseminated, fulminant, and lethal disease with multiorgan involvement.

 

35

what are 2 common parasitic infections found in AIDS patients?

1) CNS toxoplasmosis

2) Cryptosporidiosis

36

what is the most common pathogen found in diarrhea?

cryptosporidiosis

37

what is the most common focal space occupying lesions in AIDS patients?

CNS toxoplasmosis

38

what are 5 AIDS determining malignancies?

what virus causes each of these malignancies?

1) kaposi's sarcoma - HHV-8

2) Burkitt's lymphoma- EBV

3) Primary CNS lymphoma - EBV

4) Invasive cervical cancer- HPV

5) Anal squamous cell carcinoma - HPV