Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

IMM005 > Adaptive immune responses: T cells > Flashcards

Adaptive immune responses: T cells Flashcards

1
Q

What is the difference between B and T cells when it comes to their specialisation?

A

B cells stay and specialise in the bone marrow

T cells migrate to the thymus in order to specialise

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Where is the thymus located?

A

In the thoracic cavity

Next to the heart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Why is the thymus especially important in children?

A

Most T cells develop during childhood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Why are TCRs and BCRs specific?

A

Operate through a lock and key model

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Why is clonal expansion important?

A

The population of T cells with a specific TCR is low

Cells which are useful in fighting the microbes are expanded

This clonal expansion forms T cells with the same TCR which is relevant to the infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is one reason why adaptive immunity takes longer than innate immunity?

A

The T cells with the specific TCR to the antigen have to clonally expand

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the 4 features of the adaptive immunity?

A

Specificity

Diversity

Memory

Clonal expansion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the functional significance of the adaptive immune system being specific?

A

Ensures that distinct antigens elicit specific responses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the functional significance of the adaptive immune system being diverse?

A

Enables the immune system to respond to a large variety of antigens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the functional significance of the adaptive immune system having memory?

A

Leads to enhanced immune response to repeated exposures to the same antigens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the functional significance of the adaptive immune system clonally expanding?

A

Increases the small number of antigen-specific lymphocytes from a small number of naive lymphocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What percentage of T cells express TCRab?

A

90%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the T cells which express TCRab split into?

A

CD4 cells

CD8 cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What do T cells which don’t have TCRab express instead?

A

TCRyd (gamma, delta)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Why does the T cell receptor need a CD3 complex?

A

The TCR is not embedded in the T cell membrane deeply enough to transduce a signal to the cell

T CD3 molecules therefore do the signalling for the TCR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is CD3?

A

Complex of invariant chains which allows for the TCR signal to be transduced into the cell following binding with antigens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Is the CD3 signal enough for a response to be evoked upon binding with antigens?

A

No

Requires another costimulatory receptor

The most important is CD28

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is signal 1?

A

CD3 intracellular pathway activation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is signal 2?

A

CD28 intracellular pathway activation

20
Q

What happens to the T cell if it just receives signal 1?

A

Does not become activated

Becomes anergic

21
Q

How does the T cell become activated?

A

Through obtaining both signal 1 and signal 2

22
Q

What is required for the costimulatory receptors on T cells to become activated?

A

APCs need to have ligands for costimulation

These form the B7 complex

23
Q

What forms the B7 complex?

A

CD80 and CD86

24
Q

What does the nature of the immune response depend on?

A

The type of T cell which is activated

25
Q

Which cells do CD8 T cells kill?

A

Infected cells

Cancer cells

26
Q

Which MHC molecule do CD8 T cells interact with?

A

MHC I

27
Q

Through which mechanisms do CD8 T cells kill their targets?

A

Cytotoxic granules containing perforin and granzyme

Binding to death receptors on target cells like Fas

28
Q

Describe how CD8 T cells kill their targets through granzymes

A

Perforin form pores which facilitate the entry of granzymes

Granzymes cause apoptosis and cell death

29
Q

Describe how CD8 T cells kill their targets through death receptors

A

CTL can bind to death receptors on target cells

Including death receptor FasL

Upregulation of the ligand on CD8 T cells will kill the cell expressing FasR

30
Q

Describe the different types of CD4 T cells

A

Helper cells

Regulatory cells

31
Q

What is the role of CD4 regulatory T cells?

A

Inhibitory

Play an important role in autoimmunity

Suppress immune responses

32
Q

What are 3 different subclasses of T helper cells

A

Th1

Th2

Th17

33
Q

What is the marker for Th1 cells?

A

IFN y

34
Q

What is the target cell for IFNy?

A

Macrophages

35
Q

What type of pathogen do Th1 cells respond to?

A

Intracellular pathogens

36
Q

What are the markers for Th2 cells?

A

IL-4

Il-5

IL-13

37
Q

What is the target cell for Th2 cells?

A

Eosinophils

38
Q

Which pathogen do Th2 cells respond to?

A

Parasites

39
Q

What are the markers for Th17 cells?

A

IL-17

IL-22

40
Q

What is the target cell for Th17 cells?

A

Neutrophils

41
Q

Which pathogens do Th17 cells respond to?

A

Extracellular pathogens

42
Q

How do the cells of the immune system travel around in the body?

A

Blood

Lymph vessels

43
Q

How are the collections of cells in the lymph nodes connected?

A

Through lymphatics

44
Q

Apart from clonal expansion, what is another way T cells compensate for the low population of T cells with specific receptors?

A

Travel throughout the body to find microbes

45
Q

Can T cells respond to antigen straight away like B cells?

A

No

They need an antigen presentation stage

This is why the humoral immune response comes before the cellular immune response

46
Q

What is another name for the immune system under the control of T cells?

A

Cellular immune response

IMM005 (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions