15 Interactions in Adaptive Immunity Flashcards
What conditions the adaptive response to antigens?
The innate immune system
Which cells have memory?
T(TCR-MHC/peptide)
B (Ab-Ag)
NK (short memory only)
What cells “orchestrate” adaptive immunity?
T and B cells
T/F Most pathogens never activate the adaptive immune response?
True
How long does adaptive immunity take on first encounter? Second encounter?
- About 5 days to kick into gear
- Shorter
Over the time course of a virus infection, what cytokines are released in the first few days? What are the first immune CELLS that begin to attack? What cells then take over?
- IFN-alpha, IFN-Beta, TNF-alpha, IL-12
- NK’s
- T cells
How does a host cell sense virus nucleic acids?
- TLR 3,7,8,9
- RIG-I
- MDA5
Over the time course of a virus infection, in early-stage, what actions does the host take?
- 2’-5’-linked adenosine oligomers and kinase PKR
- Up MHC 1 expression, antigen presentation, and chemokines
- Activate DC’s, macrophages, NK’s
What is a T cell doubling time? How many cells can one naïve T cell produce in a week?
- 5-6 hours (about same as B cell germinal centers, fastest mammalian)
- 10,000
What third signal molecule is released to promote T cell survival during the proliferation phase?
-Bcl-2
What cytokines can provide signal 3?
IL-2,4,6,12,
IFN alpha or beta or gamma
What happens to an immune response without signal 3?
Some proliferation then dies off and produces tolerance (NOT immunity or memory)
About how long after initial infection does the immune contraction phase begin?
10 days (NOT based off clearance of infection)
Which cells expand more, CD 4 or CD 8?
CD8
T cells exhibit changes in receptors when they are naïve versus mature effectors. What are the only 2 receptors that are high in the mature stage?
- LFA-1, IFN-gamma (adhesion and effector) are high in mature, low in naive.
- All the rest are low in maturity and high in naive cells such as homing, chemokine, and cytokines.