HIV Flashcards
What is HIV?
A retrovirus that contains RNA and invades the host cell
What is HIV?
A retrovirus that contains RNA and invades the host cell
Which receptors does HIV target?
CD4+ cells
What is CD4?
A glycoprotein found on the cell surface
In which cells would you find CD4+?
T helper cells (CD4 lymphocytes)
Macrophages
Microglial cells
Dendrites
What do T helper cells do?
Cytokine release
Activate B cells
Activate killer T cells (CD8+)
Recognition of MHC2 antigen-presenting cell
What effect does HIV have on the immune response?
Reduced number of circulating CD4+ cells - taken into lymphoid tissue
Reduced proliferation of CD4+ cells
Reduced CD8+ cell activation (dysregulated expression of cytokines)
Reduced affinity of antibodies produced
Chronic immune activation
What are the normal CD4+ T helper cell parameters?
500-1600 cells/mm3
At what level of CD4+ t helper cells is there a risk of opportunistic infections?
Which receptors does HIV target?
CD4+ cells
What is CD4?
A glycoprotein found on the cell surface
In which cells would you find CD4+?
T helper cells (CD4 lymphocytes)
Macrophages
Microglial cells
Dendrites
What do T helper cells do?
Cytokine release
Activate B cells
Activate killer T cells (CD8+)
Recognition of MHC2 antigen-presenting cell
What effect does HIV have on the immune response?
Reduced number of circulating CD4+ cells - taken into lymphoid tissue
Reduced proliferation of CD4+ cells
Reduced CD8+ cell activation (dysregulated expression of cytokines)
Reduced affinity of antibodies produced
Chronic immune activation
What are the normal CD4+ T helper cell parameters?
500-1600 cells/mm3
At what level of CD4+ t helper cells is there a risk of opportunistic infections?
How long after exposure is the infection established?
3 days
What is occurring during the asymptomatic stage of HIV infection?
Ongoing proliferation of the virus
Ongoing depletion of CD4+ count
Ongoing immune activation
Risk of onward transmission
What is an opportunistic infection?
An infection caused by a pathogen that does not normally produce disease in a healthy individual - takes advantage of a weakened immune system.
Treatment for pneumocystis pneumonia?
High dose co-trimoxazole (+/- steroid) - low dose can be given prophylactically.
