NK cells Flashcards
NKs need what kind of prior stimulation
they dont
what lineage?
lymphocyte
what kind of immunity?
innate
what do NKs target?
viral, cancerous, transplant cells
cytotoxin mechanism
perforin
Ag receptor?
none.
NK cells are ___ ____ that appear to function in _____ _____
granular lymphocytes
immune surveillance
immune surveillance does what
purges precancerous cells
what lineage are they?
they arise from bone marrow but are distinct from T and B cell lineages
Where do NK cells undergo differentiation?
in the bone marrow
How does immunologic insult induce them?
it DOESNT
What cytokines increase their activity?
IL-15 and IL-2
what rxn are they the “major lymphocyte” of?
Ab-dependent cellular cytotoxicity
have membrane receptors for the Fc portion of IgG
what kind of specificity do they have?
none.
ADCC
Ab-dependent cellular cytotoxicity
what Ab do they recognize?
IgG, the Fc portion
what roles do ADCC play?
anti-viral, anti-tumor, anti-graft immunity
What cells play a role in ADCC?
NKs, macs, and neutrophils
which cells recognize IgG’s Fc portion?
NK, Macs, Neutrophils
How do they kill?
they release porforin that creates holes in the protective coats of virally/tumorous/non-self cells
How do they avoid hurting themselves with porforin?
they have a protein called protectin which binds the porforin and prevents it from causing self harm
are NK cells MHC restricted?
no. they do not need MHC molecules to recognize bad cells.
