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Flashcards in Cells of the lymphoid system Deck (25)
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1
Q

Which proteins do all T cells express?

A

CD2

CD3

CD28

CTLA4

PD1

2
Q

What are the 4 main classes of Th cells?

A

Th1

Th2

Tfh

Th17

3
Q

What two cytokines to Th1 cells produce?

A

IFNg

IL-2

4
Q

What is the role of Th1 cells?

A

Destroy intracellular pathogens

5
Q

Role of IFNg

A

Activates macrophages and help them become more adept at destroying intracellular pathogens

Released upon recognising non-native antigens presented on APCs

6
Q

Role of IL-2

A

Interaction of Th1 and APCs through CD40 and CD40L stimulates APCs to produce IL-12

IL-12 and IL-2 help proliferation of CD8+ T cells and NK cells

7
Q

Which cytokines do Th2 cells release?

A
IL-3
IL-4
IL-5
IL-9
IL-13
8
Q

What do Th2 cells protect against?

A

Allergies

Parasitic infections

9
Q

Role of cytokines secreted by Th2 cellls

A

Activation of granulocytes and mast cells

Promote class switching to IgE

10
Q

Cytokine expressed by Tfh cells

A

IL-21

11
Q

Role of Tfh cells

A

Express CD40L to interact with CD40 on B cells

Do not present antigen

Rather promote proliferation, class switching and affinity maturation in B cell follicles

12
Q

Cytokines expressed by Th17 cells

A

IL-17

IL-22

13
Q

What do Th17 cells protect against?

A

Extracellular pathogens and fungi

14
Q

Role of Th17 cells

A

Promotes neutrophil recruitment and tissue inflammation

Often present in mucosal surfaces

IL-17 stimulates other non-immune cells to produce chemokines leading to neutrophil recruitment and inflammation

15
Q

Markers of Tregs

A

CD25

FoxP3

16
Q

Two main cytokines released by Tregs

A

IL-10

TGFb

17
Q

What is the role of IL-10 secreted by Tregs?

A

Stimulates B cell proliferation

Anti-inflammatory by suppressing Th1 cells

18
Q

What important receptor do Tregs express?

A

CTLA-4

Modifies APCs through blockign or removing B7

19
Q

What is the marker of Cytotoxic T cells?

A

CD8

20
Q

4 ways in which CTLs carry out their function

A

Interact with MHC class I

Kill infected cells

Produce IFN

Activates surrounding macrophages through releasing cytokines

21
Q

What two ways do CTLs kill infected cells?

A

Death-receptor-dependent killing - interact with Fas on target to induce apoptosis

Granule-dependent killing - perforin produces pores on the membrane which allows the insertion of granzymes

22
Q

Role of IFN

A

Attempt to inhibit viral invasion of host cells through

  • inducing an antiviral state
  • inducing intracellular killing
23
Q

Which proteins do B cells express?

A

CD19

CD80/86

24
Q

Which proteins do NK cells express?

A

CD16

CD56

25
Q

What is the difference between the ways NK cells eliminate pathogens, and the way CTLs eliminate
pathogens?

A

Instead of looking for the foreign antigens, they look at the MHC itself

Cells missing MHC evade immune responses