Lesson 4.1 - HIV/AIDS Flashcards
What Baltimore classification is HIV?
Group 6; 2 (+) ssRNA; retrovirus
What enzymes are involved in HIV?
- Integrase - allows provirus to be part of host
- Protease - involved in building HIV at cell membrane; cuts polypeptides
- Reverse transcriptase
What glycoprotein spikes are involved with HIV?
gp120 and gp41
What is the viral capsid made of?
p24
What is tRNA used for in HIV?
- used as a primer for DNA synthesis
- short segment of ds nucleic acid; provides a 3’ OH
HIV is a descendant of _______.
-
Simian immunodeficiency virus (SIV)
- Same capsid, different envelope as HIV
What are the predominant strains of HIV?
- HIV-1
- HIV-2
What is HIV-1?
- Derived from SIVcpz
- Chimps in Central Africa
- 95% of human infections
- Mutation 1 million times faster
- Serogroups w/ 50-60% difference in envelope proteins
What is HIV-2?
- 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
How is HIV transmitted by?
- Anal, vaginal, and oral sex
- Plasma, semen, intestinal secretions, CSF
- Mother to child (in utero)
- If it’s dried, it’s died
What are CD4 cells?
Include monocytes (dendritic cells, macrophages) and TH
HIV requires both ____ and ____ for entry
-
CD4; co-receptor
- gp120 binds CD4
- gp41 binds co-receptor
HIV-1 enters CD4 cells via ____
-
fusion
-
Conformational change in gp41 and gp120
- Hydrophobic gp41 contacts gp120, which binds to CCR5
-
Conformational change in gp41 and gp120
Who is Stephen Crohn?
Man who can’t catch AIDS
CCR5-Δ32
Who is Timothy Ray Brown?
Received stem cells transplant for myeloid leukemia w/ CCR5-Δ32 = majority of his CD4 immune to HIV
Who is Adam Castillejo?
- 2nd individual to receive CCR5-Δ32 stem cell transplant; Hodgkin lymphoma
- ~99% of CD4 immune to HIV
How does HIV exit?
By budding
Transcription of the viral mRNA only begins after the CD4 cell is ______
activated
How is TC, NK, and Dendritic cells related to HIV?
- TC (CD8) & Natural Killer Cells attack infected TH
- Dendritic cells trap HIV and deliver it to CD4 cells
What is AIDS?
- Acquired Immune Deficiency Syndrome
- Caused by HIV
- Appears 5/10/20 yrs after HIV infection
- TH cell below 200 uL (mm3)
- Normal is 500 - 1600
What opportunistic/rare infections do HIV/AIDS patients suffer and die from?
- Candiasis of bronchi, trachea, esophagus, lungs
- HSV-1 on lips and mouth
- Salmonella diarrhea; Cytomegalovirus diseases, Toxoplasmosis, Coccidioidomycosis, Cryptococcosis
95% HIV+ develop Abs w/in _ weeks
99% HIV+ develop Abs w/in _ weeks
4; 12
What tests can be used to detect HIV/AIDS?
- 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.
What are the stages of HIV/AIDS?
- 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
Why hasn’t a vaccine developed for HIV?
- Reverse transcriptase is sloppy
- Antigenic shift
What is Anti-Retroviral Therapy (ART)?
-
RIP MEN
- _Reverse transcriptase i_nhibitors
- Integrase inhibitors
- Protease inhibitors
- Maturation inhibitors (bind to peptides - stop protease)
- Entry / fusion inhibitors (attach to TH)
- Nucleotide / nucleoside analogues (mimic nucleotides)
U = U
- Undetectable = Untransmittable
- Condoms not required to prevent HIV tranmission
Describe PARTNER 1 (2010-14).
- 888 serodiscordant couples
- 548 hetero = 36000x
- 340 gay couples = 22000x
- None of HIV- partners became +
Describe PARTNER 2 (2014-18).
- 972 gay couples (480 from PARTNER 1) = 76991x
- 15 HIV- became HIV+
- Every case, was from a different partner
Describe Pre-exposure Prophylaxis (PrEP)
- Anti-retroviral drugs
- Reduce chance of transmission by 100x
Post-exposure prophylaxis (PEP)
- Exposure to HIV via sex partner, sexual assault, needle stick
- Start w/in 72 hours
- 28-day course
Statistics of HIV/AIDS in US
- 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
Charts of HIV Incidence (13 years and older)
Idk
New HIV Diagnoses in US and Dependent Areas by Race/Ethnicity, 2018
- 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
More Charts (lmao)
Idk
HIV/AIDS - HVB & HVC
- 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
HIV/AIDS - TB
- 1/3 of 40 mil. HIV+ indiviuals co-infected w/ TB
- Leading cause of death of HIV+ ppl
HIV - Syphilis
- 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
