Brainscape's Knowledge GenomeTM

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


See full index

Immunology > T cell antigen recognition T cell activation > Flashcards

T cell antigen recognition T cell activation Flashcards

1
Q

L selectin is expressed by naive T cells and binds to

A

CD34//GLYCam-1

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

LFA-1 binds to

A

ICAM1 on HEV for the adhesion to the HEV

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

T cell to APC cell use what adhesion molecule interactions? LFA-1, CD2, and ICAM3

A

LFA-1 –> ICAM1 or 2, CD2–> LFA3, ICAM3-LFA1

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

Dendritic cells are most efficient to present

A

viral peptide antigens/ extracellular

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

Macrophages are most efficient for presentation of

A

extracellular, independently replicating organisms (Bacteria/yeast) can also present intracellular antigens

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

B cells most efficiently present peptide from

A

soluble antigens (intracellular and extracellular antigens)

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

Antigen presenting cells (APCS) express a costimulator molecule

A

B7

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

B7 binds to (on APC)

A

CD28 (on the T cells)

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

two signals for activation of T cells

A
  1. binding of its TCR to cognate peptide on MHC

2. co stimulation of B7 (APC) to CD28 (T Cell)

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

Immature dendritic cells function is to

A

take up antigen (Mature dendritic cells no longer take up antigen)

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

Mature dendritic cells express co stimulatory molecules

A

B7.1 and B7.2 and high levels of MHC class I and II molecules

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

Mature dendritic cells express what adhesion molecules?

A

ICAM1, ICAM2, LFA1, LFA3

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

Dendritic cells also express a chemotactic cytokine that attracts naive T cells

A

DC-CK

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

resting macrophages express very low levels of ? and do not express?

A

low levels of MHC class II and low levels of B7!

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

Without a costimulation signal, the macrophages induce anergy, a process called

A

peripheral tolerance

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

Once ingest microorganisms, macrophages will up regulate their expression of what molecules?

A

MHC Class II and B7

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

B cells activation process

A
  1. BCR binds to soluble antigen, produces activation signal

2. B cell internalizes and process antigen, presents peptides on MHC Class II molecules

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

B cells readily present antigen to antigen specific

A

CD4 T cells, T cells will produce 2nd signal of activation if they are effector T cells

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

T cell activation signals

A
  1. encounter with specific peptide antigen bound to an MHC molecule on APC
  2. CD28 on T cell interaction with FB7 on APC
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Signaling of CD28 and B7, increases/stabilizes/upregulates

A

IL-2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

T cell that recognizes specific antigen bound to MHC, but has no costimulation signal will become

A

anergic, peripheral tolerance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

CD8 T cells must be activated by

A

dendritic cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Produced by activated T cells upon activation

A

IL-2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Which IL can promote T cell proliferation? and promotes differentiation into armed effector T cells?

A

IL-2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Moderate affinity IL-2 receptor has what chains?

A

beta, gamma

26
Q

when resting T cell encountered specific antigen, it produces IL2 and

A

alpha chain of IL2 receptor

27
Q

Armed effector T cells do not require what?

A

costimulation signal (B7: CD28)

28
Q

Armed effector T cells express high levels of which adhesion molecules?

A

LFA-1, CD2, VLA-4

29
Q

TH1 CD4 cells are primarily involved with recognizing MHC Class II molecules on

A

macrophages and b cells

30
Q

CD8 T cells recognize peptide antigens on

A

MHC Class I

31
Q

TH2 CD4 cells recognize peptide antigens bound to

A

MHC Class II on B cells

32
Q

Which T cell promotes class switching and somatic hypermutation ?

A

TH2 CD4: induce B cells to produce other isotopes of Ab

33
Q

What do TH1 CD4 t cells induce B cells to

A

produce Ab that are efficient for opsonization (IgG1 and IgG3)

34
Q

What cytokines usually cause CD4 Th0 cells to become TH1

A

IL-12, IFN-gamma

35
Q

IL-12 is produced by ? and when?

A

macrophages and dendritic cells in response to viral and some intracellular bacterial infections

36
Q

NK cells produce IFN-gamma for?

A

to inhibit development of TH2 cells

37
Q

CD4 TH0 activated to become TH2 in presence of what?

A

IL-4, 5, 6

38
Q

Which cytokines inhibit generation of TH1

A

IL-4, IL-10

39
Q

TH2 cells produce what? inactivates growth of TH1

A

IL-10, TGF-beta

40
Q

Self antigen specific T cell receptors can be found on what?

A

regulatory T cells

41
Q

What surface protein is found on Tregs?

A

CD25

42
Q

Tregs express a transcriptional repressor known as

A

FoxP3

43
Q

In presence of TGF-beta, TH0 differentiate into

A

Tregs

44
Q

Tregs recognize

A

self-determinants

45
Q

IPEX (immune dysregulation, polyendocrinopathy, enteropathy, x linked syndrome) deficiency in

A

FoxP3

46
Q

Th17 produce what interleukins?

A

IL-17, IL-21, IL-22

47
Q

TH17 promote what influx?

A

neutrophil

48
Q

deficiency of Th17 cells can leave patient susceptible to

A

opportunistic pathogens

49
Q

VLA-4 is an integrin on surface of EFFECTOR t cells that binds to

A

VCAM-1 of activated vascular endothelial cells for transmigration of effector T cells out of vasculature

50
Q

lower than normal levels of IgM but almost undetectable quantities of IgG or IgA in serum. lymph biopsy reveals near total lack of germinal center formation. Non-sense mutation of?

A

IL-2.
Normal numbers of B cells and T cells. B cells appear to be functional because of IgM. Defect that prevents him from mounting CD8 or CD4 mediated immune responses. IL-2 is required for proliferation and differentiation after activation. Patients with this defect can’t make CD4 or CD8 T cell response, can’t activate B cells

51
Q

IL-4 deficient patient, more susceptible to?

A

extracellular pathogens

52
Q

IL-12, IFN-gamma deficient patient more susceptible to?

A

intracellular pathogens (no TH1 response)

53
Q

Heightened susceptibility to viral, bacterial, fungal pathogens. SCID. elevated serum concentrations of IgM, but almost undetectable concentrations of other antibodies. normal levels of all immune cells in circulation. Normal architecture, except total lack of germinal centers Clinical history shows what?

A

Lack of B7 expression on macrophages and dendritic cells isolated from secondary lymphoid tissues. No ability to produce B7, unable to activate T cells (CD4 and CD8). SCID patients.

54
Q

Deficiency in VCAM-1 or VLA4 would prevent effector T cells from what?

A

migrating from circulation into inflammatory sites.

55
Q

GATA3 drives transcription of cytokines by

A

Thelper 2 type effector CD4 T cells. (heightened susceptibility to extracellular pathogens)

56
Q

T-bet drives expression of cytokines by

A

T helper type 1 cells. (heightened susceptibility to intracellular pathogens)

57
Q

Thelper17 cells produce? what does this do?

A

IL-17, IL-22 that promotes production of antimicrobial peptide/proteins by epithelial cells

58
Q

Most important immune response for clearance of most viral infections is an acquired response that allows for high specificity detection and killing of virally-infected cells early in replicative cycle. What is this?

A

Cytotoxic T lymphocytes are effectors of this response.

T helper 1 type T cells are next because they produce cytokines that activate CD8 t cells.

59
Q

What type of antigen presentation would be expected with someone that has inflamed laceration of right arm and white exudate (pus)?

A

PUS: rules out viral infection and intracellular bacterium. Extracellular: pathogen would be via MHC class II pathway. CD4 cells. B cells and dendritic cells can take up bacterial, but macrophages take them up much more efficiently. B cells would have to have a BCR that has specificity for that single pathogen.

60
Q

Highly prone to activate self-reactive T cells, variety of autoimmune conditions developed. most likely cause?

A

Lack of T reg cell functionality. self-reactive effector CD4 T cells subset. Recognize cognate peptide determinant, produce anti-inflammatory cytokine TGF-beta that acts on nearly T cells that prevents from being activated (prevents activation of self-reactive T cells). FoxP3 drives expression of TGF-beta by Treg cells.

61
Q

GATA-3 drives cytokine expression by

A

TH2 effector cells

62
Q

T-bet transcription factors drive cytokine expression by

A

TH1 effector cells.

Immunology (5 decks)

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