NK cells and Gamma/Delta T cells Flashcards
(39 cards)
what are the 3 states that regulate NK cell targeting
- protection- healthy cells express both stimulatory and inhibitory signals
- Missing-self- reduced MHC I expression
- Induced-self- unhealthy cells increase stress ligand expression
T/F Not all NK cells detect all MHC I receptors or stress ligands
true
what must NK cells be in order to detect lack of receptor expression
the must be educated
what role do cytokines play dealing with NK cells
stimulating signal
receptor expression
IFNs, IL-12
what are the two activating receptors on NK cells
NKG2D
CD16 (Fc receptor)
what are the two inhibitory receptors on NK cells?
NKG2A
KIR family
can NK cells form memory cells?
yes
T/F stimulating signals must overcome inhibitory signals?
true
what does the NKG2D bind?
binds MIC proteins (stress ligands)
what does NKG2A bind?
binds MHC I
what does Killer-cell Immunoglobulin-like Receptor (KIR) family bind?
binds MHC I
inhibit activation
generally inhibitory receptors bind what?
MHC I
does cells express NKG2A and KIR at the same time?
no, there express one or the other
infected cells do what with there surface ligands
MHC I down regulation
increase stress ligand signaling
if a NK detects MHC I on a cell surface what happens?
nothing, the cell stays alive
if a NK doesn’t detect a MHC I on the surface what happens?
kills the cell
what is NK cell education
MHC I exposure during development
what are the three absolute things that happen after education
NK cells detect that specific MHC I isotype
NK cells must detect that MHC I isotype
NK cells only detect that MHC I isotype
NK cell activation and effector response
target cell response
target cell interaction:
- downregulation MHC I
- stress ligands
- CD 16
NK cell activation and effector response
leukocyte interaction
APCs
Th cells
NKT cells
NK cell activation and effector response
cytokines
IFNs, IL-12
proliferation, receptor expression, cytokine and granule production
effector functions
cytokine release
cytotoxicity
for NK cells to be activated you need what?
at least 2 stress signals and a downregulation of MHC I
Innate mechanism to activate NK cells
2 signals
stress ligands