Chapter 9: Overview of T Lymphocyte Activation Flashcards Preview

Abbas > Chapter 9: Overview of T Lymphocyte Activation > Flashcards

Flashcards in Chapter 9: Overview of T Lymphocyte Activation Deck (59):
1

Activation site of naive T cells.

Lymph nodes (peripheral lymphoid organs).

2

Cell type that presents antigen to naive T cells.

Dendritic cells.

3

Action of effector T cells in lymph nodes.

Help B cells.

4

Action of effector T cells that migrate to the site of infection.

Activate macrophages and other functions to eradicate the microbe.

5

What 2 type of T cells are generated from naive T cells.

1) Effector T cells
2) Memory T cells

6

What cytokine do activated CD4 T cells secrete?

IL-2

7

What is the action of CD4+ effector T cells?

Activate B cells, macrophages and other cells. Inflammation.

8

What is the action of CD8+ effector cells?

Activate macrophages. Kill infected cells.

9

Main function of effector T cells.

Eliminate microbes.

10

What happens to the T cell response as antigen is eliminated.

The T cell response decreases.

11

What is the first signal of T cell activation?

Antigen.

12

What is the second signal of T cell activation.

Co-stimulation.

13

APCs activated by microbes and the innate immune response increases the expression of what?

B7 costimulator.

14

What does B7 on APCs bind to?

CD28 on T cells.

15

What does CD28 on T cells bind to?

Costimulatory molecules B7-1 (CD80) and B7-2 (CD86) that are expressed on the surface of activated APCs.

16

What cytokine stimulates differential of naive T cells into effector T cells?

IL-2.

17

Signaling intermediates of T cell activation by costimulation of CD28.

PI-3 kinase/Akt
RAS/MAP kinase

18

Functional effects of T cell activation by costimulation of CD28.

Increased Bcl-X and Bcl-2 (cell survival).
Increased IL-2 and IL-2R (cell proliferation).

19

B7 family ligands found on APCs.

B7-1, B7-2, ICOS-L, PD-L1, PDL-2.

20

CD28 family member receptors found on naive T cells.

CD28, CTLA-4, ICOS, PD-1.

21

What receptor is best understood after CD28 on T cells?

ICOS.

22

What is the function of ICOS.

T-cell dependent antibody responses (germinal center reaction).

23

What 2 receptors on T cells inhibit the function of CD28?

CTLA-4 and PD-1.

24

How does CTLA-4 function as an inhibitor?

It binds more strongly to B-7.

25

How does PD-1 function as an inhibitor?

It ​delivers inhibitory signals that block signaling by the antigen receptor and by CD28.

26

Where is CD40L located?

On T cells.

27

Where is CD40 located?

On APCs.

28

What is the function of CD40L + CD40 binding?

Increase the expression of B7 on dendritic cells.

29

What is the function of the CTLA-4-Ig fusion protein?

It binds B7 and blocks the interaction of B7 with CD28.

30

What is the function of CD69?

Retain T cells in the lymph nodes.

31

What is CD25?

IL-2R.

32

What is the function of IL-2R?

T cell proliferation.

33

What is the function of CD40L?

Amplification of effector T cell function.

34

What is the function of CTLA-4?

Control T cell activation response.

35

IL-2 interaction with how many chains of the IL-2R?

3 chains.

36

Function of IL-2.

T cell proliferation.

37

High-affinity IL-2Rs are transiently expressed on activation of what cells?

Naive and effector T cells.

38

High-affinity IL-2Rs are always expressed on what cells?

Regulatory T cells.

39

Role IL-2 on naive T cells.

Effector and memory T cells proliferation and differentiation.

40

Role of IL-2 on effector T cells.

Regulatory T cell survival.

41

Which cell population (CD8+ or CD4+) are greater during an infection?

CD8+ (CD8+ > CD4+).

42

What chemokine results in central memory T cells homing to lymph nodes?

CCR7 (and L-selectin).

43

Lack of what chemokine results in effector memory T cells homing to peripheral tissue?

CCR7 (and L-selectin).

44

What are 2 types of memory cells?

Central memory T cells and Effector memory T cells.

45

What is the advantage of tissue resident memory cells?

They provide a rapid response.

46

What cytokine maintains memory T cells?

IL-7 (promotes apoptotic protein).

47

What chemokine results in co-localization of naive T cells and dendritic cells to lymph nodes?

CCR7.

48

Major costimulators on APCs required for naive T cell activation.

B7-1 (CD80) and B7-2 (CD86).

49

Function of Ig FC portion of ​CTLA-4-Ig.

​Prolongs half-life, not involved in the immune inhibitory function of the drug.

50

Number of chains of the IL-2 receptor on naive cells?

2 chains of the IL-2 receptor which bind IL-2 with low affinity.

51

Number of chains of the IL-2 receptor after antigen and costimulatory signals?

3 chains. Antigen and costimulatory signals induce IL-2 production and expression of a third chain (CD25) of the receptor, which increases the affinity for IL-2.

52

Do CD8+ or CD4+ undergo greater clonal expansion?

CD8+.

53

Production of what defines Th1 cells?

IFNγ.

54

Production of what defines Th2 cells?

IL-4, IL-5, and IL-13.

55

Production of what defines Th17 cells?

IL-17A, IL-17F, and IL-22.

56

What are the 3 master regulators?

1) T-bet
2) GATA3
3) RORγT

57

Th1 cells are associated with what master regulator?

T-bet.

58

Th2 cells are associated with what master regulator?

GATA3.

59

Th17 cells are associated with what master regulator?

RORγT.