Brainscape's Knowledge GenomeTM

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


See full index

Immunology 2.0 > Lecture 9: Activation of T Lymphocytes > Flashcards

Lecture 9: Activation of T Lymphocytes Flashcards

1
Q

The proliferation of T lympohcytes and their differentiation into effector and memory cells reuires what three signals

A
  • Ag recognition (signal 1)
  • Costimulation (signal 2)
  • Cytokines (signal 3)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Activation of naive T cells requires recognition of Ag presented by ____ meanwhile effector T cells can recognize Ags presented by ____ and _____

A

Naive T cells require DCs

Effector T cells can recognize Ags presented by Tissue macrophages and B cells

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

Superantigens (Sags) bind simultaneously

A
  • MHC class II molecules (not in the peptide-binding groove) and the V region of the beta subunit of the TCR
  • this leads to T cells produce massive amounts of cytokines (such as TNF-alpha, IL-1beta, and IL-2) which may lead to shock
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The best characterized costimulatory pathway in T cell acitvation

A
  • T cell surface receptor CD28
  • binds costimulatory molecules B7-1 (CD80) and B7-2 (CD86) expressed on activated APCs
  • B7 costimulators are regulated and ensure that T lympocyte responses are initiated only when needed.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

CTLA-4-mediated immune checkpoint is induced in naive T cells at the time

A

of their intial response to Ag

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

The stronger the stimulation through the TCR and CD28 the greater the amount of ___ that is deposited on the T cell surface from the inracellular vesicles

A

CTLA4

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

Inflammatory signals in the tissues have what effect on expression of PD1 ligands

A
  • induce expression of PD1
  • this is a way to downregulate the activity of T cells and thus limit collateral tissue damage in response to a microorganism infection in that tissue.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

No other cytokine can replace ____ for the mainenance of functional Treg cells

A

IL-2

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

CD69 binds to and reduces surface expression fo the ________ receptor _____

A
  • Sphingosine-1-phosphate receptor S1PR1
  • as a result, activated T cells are retained in the LNs long enough to receive the signals that initiate their proliferation and differentiation into effector and memory cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

IL-2Ralpha is also known as CD___

A

CD25

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

What are the inhibitory receptors on T cells

A
  • CTLA4
  • PD-1
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

various regulatory mechanisms contribute to the normal contraction of T cells, such as:

A
  • The inhibitory receptors CTLA4 and PD-1
  • Apoptosis induced by death receptors TNFRI and Fas
  • Treg cells
  • (not that IL-2 secretion decreases as well)
17
Q

The vast majority of memory T cells reside in

A

tissue sites, including lymphoid tissues, intestines, lungs and skin

18
Q

What transcription factor promotes the generation of T memory cells

A

Blimp-1

19
Q

The number of memory T cells specific for any Ag is ____ than the number of naive cells specific for the same Ag

A

greater (typically 10-100 fold more than the pool of naive cells)

20
Q

What cytokines induce the expression of anti-apototic proteins and stimulate low-level proliferation of memory cells

A

IL-7 and IL-15

21
Q

memory T cells pass through what three distinct phases

A
  • Memory generation
  • memory homeostasis
  • immunosenescence
22
Q

What are the phenotypic markers for memory T cells

A
  • IL-7R
  • CD45
  • CD27
23
Q

The central memory T cells (Tcmcells) express the chemokine receptor ____ and _____ and home mainly to

A
  • The central memory T cells (Tcmcells) express the chemokine receptor CCR7 and L-selectin and home mainly to LNs, spleen, and circulate in the blood
    • Proliferate (high production of IL-2) and generate many effector cells on Ag challenge
24
Q

Effector memory T cells (TEMcells) circulate in the blood. They do not proliferate but produce

A
  • IFN-gamma and TNF or become cytotoxic
25
Q

Resident tissue memory T cells (TRMcells) reside in epithelial barrier tissues at the interface between the host and environment. They produce

A

IFN-gamma and TNF and are specific for pathogens and other Ags that have been encountered previously though that barrier epithelium

26
Q
A
27
Q

CD69 binds to and reduces surface expression of the

A
  • sphingosin 1-phosphate receptor (S1PR1)
    • As a result, activated T cells are retained in the LNs long enough to receive the signals that initiate their proliferation and differentiation into effector and memory cells
28
Q

Expression of CD40L (CD154) is highly increased in activated T cells within ___ to ___ hours after Ag recognition

A
  • 24-48 hours

Immunology 2.0 (25 decks)

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