Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

D2 Summer > Microbio Week 5 Part 1 (Exam 2) > Flashcards

Microbio Week 5 Part 1 (Exam 2) Flashcards

1
Q

Receptors of adaptive immunity are ________

A

clonal

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

What do T cells express?

A

T cell receptors

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

What do T cell receptors recognize?

A

Peptides displayed by MHC molecules

(processed antigen is recognized)

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

Membrane-bound heterodimeric protein composed of an alpha chain and a beta chain. Has a variable region and a constant region

A

T cell receptor

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

MHC class I has variable domains of which chain(s) for the T cell receptor to bind to?

A

Alpha chains

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

MHC class II has variable domains of which chain(s) for the T cell receptor to bind to?

A

Alpha and beta chains

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

What part of gene segments accounts for the diversity in T cell receptors?

A

Somatic recombination

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

Describe recombination of T cell receptor gene segments and recombination of immunoglobulin genes

A

Both are random selection of segments

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

What is recombination of T cell receptor gene segments mediated by?

A

Lymphocyte-specific VDJ recombinase that brings 2 segments close together

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

What is the 1st step of recombination of T cell receptor gene segments?

A

Recombination of D and J segments

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

What is the 2nd step of recombination of T cell receptor gene segments?

A

Recombination of V segment w/ fused D-J element

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

What is the 3rd step of recombination of T cell receptor gene segments?

A

Recombination of C segment w/ fused V-D-J element

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

T/F: There is not a lot of T cell receptor diversity

A

FALSE; there is TREMENDOUS diversity

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

How do T cells mature and get selected?

A

+ and - selection based on functional antigen receptors

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

What does a double negative T cell mean?

A

+ selection for ability to recognize antigen

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

What does a double positive CD4+ CD8+ T cell mean?

A

negative (-) selection

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

What does a single positive CD4+ or CD8+ T cell mean?

A

+ selection based on MHC reactivity

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

Where are T cells produced? Where do they mature?

A

Produced = bone marrow
Matured= thymus

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

Pre-T cells express one chain of antigen receptor (TCRbeta). What is it called?

A

Pre-TCR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What does pre-TCR promote?

A

Cell survival

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

What do immature T cells express? (2)

A
  1. Complete TCR that promotes cell survival
  2. CD4 and CD8
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

T cells that do not express __________ __________ will die

A

functional receptors

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

What type of recognition of MHC+peptide leads to selection? What type of T cells will be selected?

A

Weak recognition

Selected T cells = single +

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

What type of recognition of MHC+peptide leads to death?

A

Strong recognition
No recognition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Strong recognition leads to ...
negative (-) selection, death
26
Weak recognition leads to ...
+ selection, periphery
27
No recognition leads to ...
Neglect, death
28
What allows T cells to be selected and migrate to the periphery?
Appropriate amount of antigen recognition in the thymus
29
What leads to clonal expansion? (in other words, how are T cells activated?)
Antigen recognition Costimulation
30
Where do naive T cells circulate in search of their antigens?
From lymph node to lymph node
31
What signals are provided by Thelper cells to help macrophages and B cells?
CD40L IFNgamma
32
What is the difference between naive and effector T cells in a situation in which there is an infection?
Effector T cells contract following clearance of pathogens
33
What is necessary for thymocytes to survive and mature in the thymus?
Expression of preTCR and TCR
34
What is the function of Th17 cells in response to infection?
Recruit neutrophils to the mucosa for clearance of extracellular microbes
35
How do activated cytotoxic T cells (CTL) kill cells infected with an intracellular microbe? What activates them?
Activated by dendritic cells Receive help from Thelper cells to produce perforin and granzyme which lyse infected cell
36
Cytokines produced by dendritic cells and other innate cells determine the fate of naive T cells and the cytokine they will produce. What cytokines accurately induce Th cell differentiation? IFNgamma induces Th2 IL-12 induces Th17 IL-6 induces Th1 IL-5 induce Th17 IL-4 induces Th2
IL-4 induces Th2
37
CD28 ligand and cell
B7-APC
38
CD40L ligand and cell
CD40-APC
39
MHC-I ligand and cell
TCR-CD8
40
MHC-II ligand and cell
TCR-CD4
41
IL-2 ligand and cell
IL-2R-T cells
42
What happens to T cells after they migrate to antigen sites in tissues?
Reactivated Carry their function
43
During costimulation of T cell activation, antigen recognition (signal 1) alone induces what?
Unresponsiveness
44
During costimulation of T cell activation, engagement of B7 on APC by CD28 on T cells provides signal 2 and induces what?
Proliferation
45
What are inhibitory receptors in T cells critical for?
Limiting/terminating immune responses
46
Concomitant activation of CD4 T cells provides help to CD8 T cells via ...
IL-2 production (proliferation, differentiation)
47
Clonal expansion means
Growth
48
Contraction (homeostasis) means
Death
49
Antigen-specific T cell clones ____________ in response to antigens. This provides a large pool of effector cells to fight the infection
expand
50
When there's an infection, which cells exhibit greater clonal expansion, CD8 or CD4 T cells?
CD8 T cells
51
Naive T cells ____________ and ______________
proliferate; differentiate
52
What type of T cells can proliferate and differentiate?
Naive T cells
53
Most effector T cells leave the lymph node, except for which ones?
T follicular helper cells (Tfh)
54
What is the function of T follicular helper cells (Tfh)?
Help B cells
55
What is the effector function of CD4 helper T cells (what do they activate)?
Activate phagocytes Activate B cells to produce Ig
56
How do CD4 helper T cells activate phagocytes?
CD40-CD40L IFNgamma production
57
How do CD4 helper T cells activate B cells to produce Ig?
CD40-CD40L Cytokine production
58
What allows for T cell movement/migration?
Adhesion molecules + chemokine receptor
59
What are the 2 types of cell-mediate immunity?
CD4 helper T cells CD8 cytotoxic T cells
60
What do CD4 helper T cells produce?
Cytokines that activate & recruit other cells
61
What do CD8 cytotoxic T cells do?
Kill infected cells
62
T/F: Recognition of antigens by T cell receptors is very specific
True
63
T cell clones express T cell receptors that can only recognize _____ peptide/MHC complex
1
64
Only _____ peptide/MHC complex can fit into a T cell receptor
1
65
T/F: Presentation of antigen to T cells by APC is very diverse
True
66
Several peptides can be presented by different MHC I and MHC II molecules on the surface of the same _________ _______
dendritic cell
67
What do T cells patrol in search of antigens with the perfect fit?
Lymph nodes
68
What cytokine does Th1 make?
IFNgamma
69
What does Th1 target?
Macrophages
70
What does Th1 defend against?
Intracellular pathogens
71
What is the role of Th1 in disease?
Autoimmunity Chronic inflammation
72
What cytokine does Th2 make?
IL-4 IL-5 IL-13
73
What does Th2 target?
Eosinophils
74
What does Th2 defend against?
Parasites (helminths)
75
What is the role of Th2 in disease?
Allergy
76
What cytokine does Th17 make?
IL-17 IL-22
77
What does Th17 target?
Neutrophils
78
What does Th17 defend against?
Extracellular pathogens
79
What is the role of Th17 in disease?
Autoimmunity
80
What are 3 CD4 helpter T cell subsets?
Th1 Th2 Th17
81
What are different cytokines produced by?
Dendritic cells (or other innate cells that have recognized different types of microbes)
82
What do cytokines determine the fate of?
Naive T cells
83
Activation of macrophages by Th1 cells involves what? (2)
CD40L-CD40 IFNgamma-IFNgammaR
84
IL-4 induces what?
B cells to produce IgE
85
IL-5 induces what?
Eosinophil activation
86
What is classically activated macrophage (M1) responsible for?
Killing and inflammation
87
What is alternatively activated macrophage (M2) responsible for?
Tissue repair Inhibit inflammation
88
IL-17 and IL-22 induce what?
Antimicrobial peptide production by epithelial cells
89
What does IL-17 mediate?
Recruitment of neutrophils
90
How does the recruitment of neutrophils (mediated by IL-17) occur?
Via induction of cytokine/chemokine production from other cells
91
What cytokine do T follicular helper cells produce?
IL-21
92
What does IL-21 mediate the production of?
Ig by B cells
93
What cells are cytotoxic T cells most similar to?
NK cells
94
How do cytotoxic T cells mediate their function? (2)
Recognition of antigens Killing via perforin and granzyme
95
How do CD8 cytotoxic T cells kill?
Release perforin and granzyme from granules
96
What must Th1 cells activate to lyse intravesicular microbes?
Macrophages
97
________ kills infected cells with help from _______
CD8; Th1
98
What do B cells express?
B cell receptors
99
What type of receptor? Membrane-bound antibodies in association with invariant membrane proteins Ig-alpha and Ig-beta
B cell receptor
100
What is the structure of immunoglobulins?
Y shape 2 heavy chains 2 light chains
101
How many forms of immunoglobulins are there? Name them
2 forms: membrane-bound and secreted
102
What region of the immunoglobulin contains the antigen-binding site?
Variable region
103
What region of the immunoglobulin mediates effector function?
Constant region
104
What does the constant region of the immunoglobulin determine?
The isotype
105
What does the constant region of the immunoglobulin bind to? (2)
1. Complement 2. Fc receptors
106
Which part of the immunoglobulin is this describing? Variable domains of light and heavy chains
Binding site
107
Which antigen is recognized by immunoglobulins, native or processed?
Native antigen
108
Antigen part recognized by antibody
Epitope
109
What leads to production of IgM?
C gene organization
110
What is the first C region cluster to be produced?
Cu
111
What is the first antibody to be produced?
IgM
112
T/F: There is tremendous diversity in the generation of immunoglobulins
True
113
Steps in the maturation of lymphocytes
1. Proliferation and receptor expression 2. Immature cells that do not rearrange functional receptors die (apoptosis) 3. Mature cells undergo + or - selection

D2 Summer (37 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions