HIV/AIDS Flashcards
gp120
on HIV
binds CD4 causing a conformational change allowing CCR-5 to bind CD4: p120 complex
CCR-5
on CD4 T cell
receptor on CD4 cell that binds gp120
gp41
on HIV
membrane penetration of CD4 T cell
APOBEC3G
apolipoprotein B mRNA-editing, enzyme-catalytic, polypeptide-like 3G
Naive T cell enzyme
cytidine deaminase: cytosine to uracil in HIV viral DNA
prevents HIV infection of naive T cells
inactivated when T cell is activated
Vif
HIV protein that promotes APOBEC3G degradation by cellular proteases
NFkB
stimulates transcription of IL-2 and IL-2 receptor when T cell becomes activated
IkkB
holds NFkB inactive
Targets of HIV
CD4 T cell
Also
1. macrophages
2. dendritic cells
Vpr
HIV protein
allows nuclear targeting of HIV preintegration complex through nuclear pore
HIV-1
can infect and multiply in terminally differentiated non dividing macrophages
dependent upon vpr gene
reservoir of HIV infection
vacuoles of macrophages
resistant to cytopathic effects
vehicle for transport of HIV to various parts of body (ex: nervous system)
monocytes
What does damage to brain cells in HIV infections?
gp41: IL-1, TNF, IL-6, NO
gp120: direct damage
Primary HIV infection (acute phase)
6 weeks after infection
viral load: 10 million/ml
CD4 count: 500/cu mm
mucosal
Clinical HIV latency (chronic phase)
up to 10 years after infection viral load: 10,000/ ml CD4 count: 50/cu mm lymph nodes and spleen asymptomatic opportunistic infections: candidiasis, herpes, TB
Final HIV crisis phase
11 years after infection
viral load: 10 million/ml
CD4 count: 5/cu mm
long lasting fever (> 1 month), fatigue, weight loss, diarrhea
Pneumocystis jiroveci pneumonia
sym: insidious onset of dyspnea, fever, non-productive cough
signs: tachypnea
chest x-ray: bilateral hazy interstitial infiltrates, which become dense alveolar infiltrates
Test: hypoxemia
CMV: in AIDS
disseminated
enteritis (diarrhea), retinitis (visual impairment), esophagities
cryptococcus
fungus
yeast form in soil and pigeon poop
meningitis
virulence: capsule
histoplasmosis
Memphis
small yeast in fecal-enriched soil near chicken coops
caseating granulomas or diffuse pneumonia with macrophages
acute retroviral syndrome
clinical presentation of initial spread of the virus and host response
3-6 weeks after HIV infection; resolves in 2-4 weeks
nonspecific (flu-like) symptoms: sore throat, myalgias, fever, weight loss, fatigue
AIDS
in absence of HIV Tx: progresses to AIDS in 7-10 years
serious opportunistic infections, secondary neoplasms, or clinical neurologic disease
toxoplasmosis
protozoa
encephalitis
JC virus
human papovavirus
CNS infection
progressive leukoencephalopathy (infection of oligodendogliocytes)
Cancers with high incidence in AIDS patients
Kaposi sarcoma, B cell lymphoma, cervical cancer, anal cancer
immune reconstitution inflammatory syndrome
paradoxical clinical deterioration when advanced HIV are given antiretroviral therapy
