Lecture 8 - Effector T Cell Response

Question 1

What changes are seen in naive T cell priming

Answer 1

1 - forms a stable synapse
2 - increase T cell adhesiveness to APCs
3 - induction of pro-survival signal
4 - increase in metabolic activity
5 - increased transcription

Question 2

why is it necessary to increase the metabolic activity of T cells

Answer 2

for cell proliferation and production of effector molecules, receptors, integrins, etc.

Question 3

How is TCR signaling initiated

Answer 3

tyrosine phosphorylation within the cytoplasmic region of immunoreceptors (ITAMs)

Question 4

summarize:

PLC-y-mediated T-cell activation

Answer 4

1. intracellular calcium entry
2. activation of RAS
3. activation of protein kinase

Question 5

summarize:

T cell changes after TCR signaling

Answer 5

1. increased cell survival
2. increased metabolic activity
3. increased gene transcription
4. increased growth factor production

Question 6

The T cell receptor has many functional components, some of which are involved in signal transduction, while others are involved in antigen recognition. What two elements are involved in antigen recognition?

Answer 6

TCRa and TCRb

Question 7

Why are lymph nodes palpable after infection

Answer 7

rapid stromal expansion of immune response

Question 8

What antigen receptors give rise to CD4 an CD8 T cells

Answer 8

alpha and beta

Question 9

T/F: cytokines in APCs dictate what T cell differentiate to

Answer 9

True

Question 10

what are the master regulator transcription factors of CD4+ T cells

Answer 10

T-bet
GATA-4
RORyT
BcI-6
FoxP3

Question 11

T/F: T helper cells regulate

Answer 11

False - activate

Question 12

What T helper cell targets extracellular bacteria

Answer 12

TH17

Question 13

what immune cells do TH17 target for enhanced response

Answer 13

neutrophils

Question 14

What major cytokines and their actions in TH17

Answer 14

IL17 and IL22

recruit neutrophils
increase cell turnover
direct killing of bacterium on epithelium

Question 15

What T helper cell targets intracellular bacteria

Answer 15

TH1

Question 16

what immune cells do the TH1 target for enhanced response

Answer 16

macrophage

Question 17

What major cytokines and their actions have in TH1

Answer 17

IFN-y

recruit macrophages and increase phagocytotic capability
kills chronically infected cells

Question 18

What immune cell targets helminth infections

Answer 18

TH2

Question 19

what immune cells do the TH2 target for enhanced response

Answer 19

eosinophils, mast cells, basophils

Question 20

What major cytokines and their actions have in TH2

Answer 20

IL4/5

increased cell turnover and mucus
increase smooth muscle contraction

Question 21

T/F: antibodies are effective no matter where they are found

Answer 21

False - only effective while a pathogen is outside the cell

Question 22

How are cytotoxic T cells like serial killers

Answer 22

recognizes “targets” (viral-infected cell), will bind and initiate apoptosis on specific cell

Question 23

extrinsic removal

Answer 23

activation of death receptors via ligands

Question 24

intrinsic or mitochondrial removal

Answer 24

response to noxious stimuli

Question 25

what specialized protease is common to both extrinsic/intrinsic pathways

Answer 25

aspartic acid-specific cysteine proteases (CASPASES)

Question 26

Initiator caspases

Answer 26

promote apoptosis by cleaving and activating others

Question 27

Effector caspases

Answer 27

initiate intracellular breakdown for apoptosis

Question 28

Perforin

Answer 28

delivers contents of granules into the target cell cytoplasm

Question 29

Granzymes

Answer 29

activate apoptosis in the cytoplasm of the target cell

Question 30

Granulysin

Answer 30

antimicrobial actions

Question 31

summarize what happens once a cytotoxic T-cell

Answer 31

1 - perforin creates pores 2 - granzymes enter the cell and trigger mitochondria 3 - cytochrome C released 4 - caspase activation 5 - intracellular changes 6 - apoptosis

Question 32

What are the 4 steps in T cell killing of target cells

Answer 32

1 - recognition 2 - proliferation 3 - differentiation 4 - effector (killing)

Question 33

Define what co-inhibitory receptors do

Answer 33

regulate un-controlled activation of lymphocytes through competition with CD28

Question 34

What are the immune checkpoints

Answer 34

co-inhibitory molecules expressed by T cells CD152 and PD1

Question 35

ITIM

Answer 35

immunoreceptor tyrosine-based inhibitory motif

Question 36

ITIM inhibits TCR signaling through

Answer 36

dephosphorylation

Question 37

How do Tregs regulate T effector cells

Answer 37

directly or via APCs

Question 38

how does infection response progress in the body

Answer 38

1. establishment of infection 2. inductive phase 3. effector phase 4. memory phase

Question 39

What does the asymmetric division of a T cell produce

Answer 39

Helper and Memory T cell precursors

Question 40

how do corticosteroids work

Answer 40

block NF-kB responses (T cell proliferation, apoptosis of developing thymocytes, etc)

Question 41

how does tacrolimus work

Answer 41

blocks IL, IFN-y

Question 42

How does cyclosporine work

Answer 42

selective immunosuppressant blocks TH1 responses

Question 43

What 3 signals do APCs deliver to T cells

Answer 43

1. TCR activation 2. Survival 3. Differentiation

Question 44

Naive CD4+ cells differentiate to

Answer 44

TH1, TH2, TH17, THf, THreg

Question 45

TH1 secretes _____ and provides immunity against ______ bacteria

Answer 45

IFN-y and IL-2; intracellular

Question 46

TH2 secretes ______ and provides immunity against ______ bacteria

Answer 46

IL 4/5/13; helminths

Question 47

TH17 secretes ______ and provides immunity against ______ bacteria

Answer 47

IL17/22; extracellular

Question 48

THf secretes _____ and

Answer 48

IL21; help b cells isotope switching