HIV Flashcards
Lymphadenopathy Associated Virus (LAV)
Luc Montagnier at the Pasteur Institute in France
1983:
Luc Montagnier at the Pasteur Institute in France
Human T Lymphotropic Virus Ill
Robert Gallo of US confirmed the discovery of the virus
1984
Robert Gallo of US confirmed the discovery of the virus
HUMAN IMMUNODEFICIENCY VIRUS (HIV)
President Mitterand of France and President Reagan of US resolved the issue
TWO TYPES OF HIV VIRUS
HIV-1
HIV-2
: HIV virus common worldwide
HIV-1
: HIV virus isolated in Africa
HIV-2
3 Groups of HIV-1
Group M
Group N
Group O
– major group
Group M
– non m/non
Group N
– outlier group
Group O
HIV Genus
Lentivirinae
HIV Family
Retroviridae
HIV Contains 2 positive single stranded RNA
SSrNA
HIV Structure
[?] in diameter
100nm
You can get HIV from:
Sex without condom
Passed from mother to baby (Vertical and perinatal)
Sharing of equipment
Contaminated transfusion transplants and blood organ
You cannot get HIV from:
Kissing
Hugging
Sharing food
Insect bites
Toilet seats
Bathing together
Sneezes and cough
Heat
HIV main MOT
Sex without condom
Target cell of HIV:
CD4 T cells (T helper cells)
Important Proteins
Gp41/Gp120 comples
p24
p17
• Large glycoprotein that traverses the bilipid layer
Gp41/Gp120 comples
• Gp120 and CD4 complex will interact with CCR5 and CXCR4 receptors of CD4 T cells p24
Gp41/Gp120 comples
• Nucleocapsid core protein
p24
One of the earliest marker to HIV infection
p24
The presence of [?] does not mean (+) for HIV
p24
• Matrix shell protein
p17
Important Enzymes
Reverse transcriptase
Integrase
Protease
• Enables the virus to convert viral RNA to DNA
Reverse transcriptase
• (Normal process: [?])
DNA to RNA
• Inserts viral DNA into host DNA
Integrase
Making it impossible to kill the virus; ability to persist in the host
Integrase
• Cleaves other enzymes and structural proteins from their polyproteins; important in formation of new virion
Protease
• Progressive deterioration of the immune system due to the destruction of CD4 cells
HIV INFECTION
Normal CD4:CD8 ratio =
2:1
CD4:CD8 ratio With HIV =
0.5:1
can occur in HIV INFECTION
Opportunistic infections
STAGES OF HIV INFECTION
Primary Stage
Intermediate Stage
Final Stage
Acute HIV
Primary Stage
Clinical Latency
Intermediate Stage
Opportunistic infections
Final Stage
• May be asymptomatic
Primary Stage
• Development of flu-like symptoms
Primary Stage
• Lymphadenopathy
Intermediate Stage
• Fever
Intermediate Stage
• Weight loss
Intermediate Stage
• Diarrhea
Intermediate Stage
• Fatigue, night sweats
Intermediate Stage
Intermediate Stage Labs:
T4 cells < 400/mm2
CD4:CD8 ratio is <1 (vs. normal ratio of 2:1)
Thrombocytopenia, Leukopenia, Anemia
Aka HIV dormancy
Clinical Latency
Some may show s/s, while others may show little to none
Clinical Latency
Lasts 10 years or longer for some
Clinical Latency
rapid multiplication of the virus
Acute HIV
high viral load = high risk of transmission
Acute HIV
(inflamed/swollen lymph nodes)
Lymphadenopathy
Acquired Immune Deficiency Syndrome - AIDS (after 2-10 years)
Final Stage
Final Stage Labs:
T4 cells < 200/mm2
Opportunistic infections in Final Stage:
Pneumocystis jiroveci (formerly carinii)
Candidiasis
CMV
Herpes simplex
M. tb
Kaposi’s sarcoma
Hairy leukoplakia
(formerly carinii)
Pneumocystis jiroveci
HIV IMMUNOLOGIC FEATURES
- Progressive depletion of T4 cells
- Reversing the normal CD4:CD8 ratio (normal 2:1) to as low as 0.5:1
- First detectable serologic marker is the core protein p24
HIV Screening tests
ELISA
HIV Confirmatory tests
Western blot assay
Solid phase assay
ELISA
> 99.5% sensitivity
ELISA