Exam 2 Adaptive immunity Activation Flashcards
T helper cell role
to produce cytokines which will activate other immune cells
T helper cells come from
Naive CD4+ T cell
TH1 secretes ___ to activate ____
TH1 secretes IL-2 and IFN gamma to activate CD8+ cells (gamma also activates macrophages)
TH2 secretes ___ to activate ____
TH2 secretes IL-4 and IL-5 to activate B cells
B cells activated by
IL-4 and IL-5 both produced by TH2
CD8+ cells (and macrophages) are activated by
IL-2 and IL-gamma which is produced by TH1 cells (macro by gamma)
CD8+ cell function
CTL-Cytotoxic T cells: destroy infected cells (endogenous, intracellular) by releasing perforins which embed into the cell membrane-secrete granzymes into target and trigger apoptosis of infected cell; can recognize more than one cell!
CD8+/CTL cells release __ to do ___
perforins which embed –> granzymes –> apoptosis of endogenous/intracellular
Types of cells CD8+ cells kill
endogenous/intracellular infections
Number of cells CD8+ cells can recognize
Many! not one and done
TCR recognizes what
shot, processed, 8-25 a.a. long fragments of antigens presented to them by MHC
APC Cells
Antigen Presenting Cells-bind antigens, engulf them, digest, and present on surface as antigenic peptides (epitopes) to TCR
process and present antigens to TCR
APC cells
bridges between innate and adaptive
Macrophages as APCs, chronic inflammation as holding off until adaptive comes, Dendritic cells as APC, NK cells as (?) and more?
APCs
Macrophages (innate), B cells (adaptive), and dendritic cells (innate)
Dendritic cells
migratory cells that recognize pathogens nonspecifically (PAMPS)-carry antigen to lymph system-process and present antigen to T cells-deliver a costim signal to interacting T cell to activate them
Dendritic cells recognize
PAMPS non-specifically
Type of receptors APCs have (antigen binds)
MHC receptors
HLA encodes
MHC receptors in humans
MHC I presents
CD8+ cells –> cytotoxic T cells
MHC II presents
CD4+ cells –> helper T cells
Receptor all (most) cells express
MHC1-except RBC and APCS
APCs present MHC __
II
interaction of MHC with TCR
T cell receptor binds to variable parts of MHC protein to form peptide binding groove; the co receptor (glycoprotein) binds to the invariant part of the MHC protein, far away from the groove –> stabilization
TCR binds to ___ of MHC
variable part- forms the binding groove
Co-receptor (glycoprotein) binds ___ of MHC
invariant part-far from the groove
process antigens presented to APCs
proteosomes (enzyme in cell)
MHC I binds
antigens processed by proteosomes from APCS
MHC I bind what type of antigens
endogenous
binds endogenous antigens
MHC1
processed antigens from self or virally infected cells would originate on which type of receptor
MHC1 and present to CD8+
MHCI presents antigen to ____ T cells
CD8+
How do viral proteins get outside cell on MHC1
proteosomes degrade them and use ER to present on cell surface
MHCII found where
APCs only; note that APCs also have MHCI
Type of receptor on APCs
MHC I and II
MHCII receptors bind peptides generated by
lysosomal enzymes
Antigens presented on MHCII are ____ (origin)
exogenous-outside the cell (MOST bacteria, fungi, and toxins)
MHCII presents to ___
CD4+ cells
