Lesson 4.1 - HIV/AIDS

Question 1

What Baltimore classification is HIV?

Answer 1

Group 6; 2 (+) ssRNA; retrovirus

Question 2

What enzymes are involved in HIV?

Answer 2

• Integrase - allows provirus to be part of host
• Protease - involved in building HIV at cell membrane; cuts polypeptides
• Reverse transcriptase

Question 3

What glycoprotein spikes are involved with HIV?

Answer 3

gp120 and gp41

Question 4

What is the viral capsid made of?

Answer 4

p24

Question 5

What is tRNA used for in HIV?

Answer 5

• used as a primer for DNA synthesis
  
  • short segment of ds nucleic acid; provides a 3’ OH

Question 6

HIV is a descendant of _______.

Answer 6

• Simian immunodeficiency virus (SIV)
  
  • ​Same capsid, different envelope as HIV

Question 7

What are the predominant strains of HIV?

Answer 7

• HIV-1
• HIV-2

Question 8

What is HIV-1?

Answer 8

• Derived from SIVcpz
• Chimps in Central Africa
• 95% of human infections
  
  • Mutation 1 million times faster
  • Serogroups w/ 50-60% difference in envelope proteins

Question 9

What is HIV-2?

Answer 9

• Derived from SIVsm
• Sooty mangabeys in West Africa
  
  • Less virulent (not less deadly, just slower)
  • 5-10x lower transmission than HIV-1
  • 50% DNA sequence homology

Question 10

How is HIV transmitted by?

Answer 10

• Anal, vaginal, and oral sex
  
  • Plasma, semen, intestinal secretions, CSF
• Mother to child (in utero)
• If it’s dried, it’s died

Question 11

What are CD4 cells?

Answer 11

Include monocytes (dendritic cells, macrophages) and T_H

Question 12

HIV requires both ____ and ____ for entry

Answer 12

• CD4; co-receptor
  
  • ​gp120 binds CD4
  • gp41 binds co-receptor

Question 13

HIV-1 enters CD4 cells via ____

Answer 13

• fusion
  
  • ​Conformational change in gp41 and gp120
    
    • Hydrophobic gp41 contacts gp120, which binds to CCR5

Question 14

Who is Stephen Crohn?

Answer 14

Man who can’t catch AIDS

CCR5-Δ32

Question 15

Who is Timothy Ray Brown?

Answer 15

Received stem cells transplant for myeloid leukemia w/ CCR5-Δ32 = majority of his CD4 immune to HIV

Question 16

Who is Adam Castillejo?

Answer 16

• 2nd individual to receive CCR5-Δ32 stem cell transplant; Hodgkin lymphoma
• ~99% of CD4 immune to HIV

Question 17

How does HIV exit?

Answer 17

By budding

Question 18

Transcription of the viral mRNA only begins after the CD4 cell is ______

Answer 18

activated

Question 19

How is T_C, NK, and Dendritic cells related to HIV?

Answer 19

• TC (CD8) & Natural Killer Cells attack infected TH
• Dendritic cells trap HIV and deliver it to CD4 cells

Question 20

What is AIDS?

Answer 20

• Acquired Immune Deficiency Syndrome
  
  • Caused by HIV
  • Appears 5/10/20 yrs after HIV infection
  • T_H cell below 200 uL (mm³)
    
    • Normal is 500 - 1600

Question 21

What opportunistic/rare infections do HIV/AIDS patients suffer and die from?

Answer 21

• Candiasis of bronchi, trachea, esophagus, lungs
• HSV-1 on lips and mouth
• Salmonella diarrhea; Cytomegalovirus diseases, Toxoplasmosis, Coccidioidomycosis, Cryptococcosis

Question 22

95% HIV+ develop Abs w/in _ weeks

99% HIV+ develop Abs w/in _ weeks

Answer 22

4; 12

Question 23

What tests can be used to detect HIV/AIDS?

Answer 23

• Finger stick. oral/saliva Abs, Antibody/Antigen
• VIiral Load detects HIV 9-11 days after infection; DNA PCR test / NAAT

All tests should be accompanied with counseling.

Question 24

What are the stages of HIV/AIDS?

Answer 24

• Stage 1: Acute HIV Infection
  
  • 2-4 weeks after infection; flu-like
• Stage 2: Clinical latency
  
  • 2-15 years; initial immune response knocks viral load
• Stage 3: AIDS

Question 25

Why hasn't a vaccine developed for HIV?

Answer 25

* Reverse transcriptase is sloppy * Antigenic shift

Question 26

What is Anti-Retroviral Therapy (ART)?

Answer 26

* **RIP MEN** * _**​**Reverse transcriptase i_nhibitors * _Integrase_ inhibitors * _Protease_ inhibitors * _Maturation_ inhibitors (bind to peptides - stop protease) * _Entry / fusion_ inhibitors (attach to T_H) * _Nucleotide / nucleoside analogues_ (mimic nucleotides)

Question 27

U = U

Answer 27

* Undetectable = Untransmittable * Condoms not required to prevent HIV tranmission

Question 28

Describe PARTNER 1 (2010-14).

Answer 28

* 888 serodiscordant couples * 548 hetero = 36000x * 340 gay couples = 22000x * None of HIV- partners became +

Question 29

Describe PARTNER 2 (2014-18).

Answer 29

* 972 gay couples (480 from PARTNER 1) = 76991x * 15 HIV- became HIV+ * Every case, was from a different partner

Question 30

Describe Pre-exposure Prophylaxis (PrEP)

Answer 30

* Anti-retroviral drugs * Reduce chance of transmission by 100x

Question 31

Post-exposure prophylaxis (PEP)

Answer 31

* Exposure to HIV via sex partner, sexual assault, needle stick * Start w/in 72 hours * 28-day course

Question 32

Statistics of HIV/AIDS in US

Answer 32

* 1.2 million adults HIV+ (13 years and older) * 1 in 7 (14.2% unaware of infection) * 176k individuals * (2018) 36,400 new individuals * (2010-17) Deaths declined from 9/.1 to 4.7 (48%) * (2017) 16,358 died; 5,534 deaths HIV-related

Question 33

Charts of HIV Incidence (13 years and older)

Answer 33

Idk

Question 34

New HIV Diagnoses in US and Dependent Areas by Race/Ethnicity, 2018

Answer 34

* Blacks/AA= 16k (42.2%) * Hispanics/Latinos = 10.2k (27.0%) * Whites = 9.5k (25.2%) * Multiple Races = 944 * Asians = 875 * AI/AN = 186 * Native Hawaiians/PI = 68

Question 35

More Charts (lmao)

Answer 35

Idk

Question 36

HIV/AIDS - HVB & HVC

Answer 36

* HepB more likely than HepC to be transmitted sexually * 1 in 10 have HepB * 1 in 4 have HepC * Both *in utero* * IDU: Sharing needles, syringes, & other injection equipment

Question 37

HIV/AIDS - TB

Answer 37

* 1/3 of 40 mil. HIV+ indiviuals co-infected w/ TB * Leading cause of death of HIV+ ppl

Question 38

HIV - Syphilis

Answer 38

* 2- to 5-fold increasd risk of acquiring HIV when Syphilis is present * More likely to shed HIV when they have urethritis or genital ulcer * Not considered a factor that contributes to deaths of HIV+ individuals