Brainscape's Knowledge GenomeTM

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


See full index

Basic Immunology- Module 1 > Immunological Memory > Flashcards

Immunological Memory Flashcards

1
Q

What are the differences between the primary and secondary responses of B cells?

A

higher frequency of antigen specific B cells; produce IgG or IgA rather than IgM; higher affinity and higher level of somatic hypermutation

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

How can memory B cells be created?

A

either from the primary response germinal center reaction or independently of hte germinal centre reaction from short-lived plasma cells

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

Where do memory B cells take up residence?

A

spleen and lymph nodes

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

What markers distinguish memory B cells from naive B cells and plasma cells?

A

switched surface Ig isotype (rather than just IgM or IgD- whilst plasma cells have very low surface Ig; CD27 is found on memory B cells and naive T cells ; memory B cells have higher levels of MHC II and B7.1

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

what does Cd27 on memory B cells and naive T cells bind to?

A

CD70 expressed on dendritic cells

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

What is the difference between isotypes of antibody produced in the primary response vs the secondary response?

A

secondary response produces relatively little IgM; lots of IgG and some IgA and IGE

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

Why do memory cells have higher levels of MHC II and B7.1?

A

memory B cells can acquire and present antigen more efficiently to Tfh cells so they can help stimulate the antibody repsonse

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

What causes the affinity of the antibodies produced during secondary and tertiary responses to rise progressively?

A

memory B cells can reenter germinal centers and undergo additional somatic hypermutation and affinity maturation

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

What protein do memory T cells express more of than activated T cells?

A

Bcl-2 : promotes cell survivial

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

What markers do activated T cells express that memory T cells don’t ?

A

CD69

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

What important markers differentiate memory T cells from effector T cells?

A

alpha subunit of hte IL7 recceptor (expressed by naive T cells but not effector)

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

What do naive T cells require to survive?

A

require contact with self peptide:selfMHC complexes as well as IL7

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

What cytokines does the survival of memory T cells rely on?

A

IL7 and IL15 (CD8)

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

What is the homing receptor taht directs T cells into secondary lymphoid tissues?

A

L-selectin (CD62L)

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

What homing receptor is found on effector and memory T cells instead of L-selectin?

A

CD44- expressed in peripheral tissues

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

Why do memory T cells express CD44 instead of L-selectin?

A

means they can migrate from the blood into peripheral tissues rather than migrating directly into lymphoid tissues

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

What is CD45?

A

a surface protein tyrosine phosphatase expressed on all haematopoietic cells

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

What cells is the CD45RO isoform found on?

A

effector and memory T cells

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

What chemokine receptor do central memory T cells express?

A

CCR7

20
Q

What is the function of central memory T cells?

A

recirculate similarly to naive T cells, traffic throug the T zones of peripheral lymphoid tissues

21
Q

What is the pattern of migration of naive T cells?

A

migrate from the blood, into the secondary lymphoid organ then into the lymphatics and back into the blood

22
Q

What is the differnece between central memory T cells and otehr memory T cells?

A

very sensitive to cross-linking of their T cell receptor and rapidly express CD40L in response but become effectors relatively slowly

23
Q

What markers do effector memory T cells possess?

A

lack CCR7 but express b1 and b2 integrins

24
Q

What is the function of effector memory T cells?

A

rapidly enter inflamed tissues and rapidly mature into effector T cells

25
Q

What cytokines do effector T cells produce soon after stimulation?

A

IFNy; IL-4 and IL-5

26
Q

What is hte migration pattern of effector T cells?

A

migrate from blood into peripherl non-lymphoid tissues then into lymphatics–secondary lymphoid tissues–lymphatics–blood

27
Q

What is different about tissue resident memory T cells compared with central and effector memeory T cells?

A

do not migrate but take up residence in epithelial sites

28
Q

What does TGF-b production by epithelial cells cause in the Trm?

A

Trm cells express ae:b7 which binds E-cadherin expressed by the epithelium and is required for Trm retenion

29
Q

What happens when Tcm cells are stimulated by antigen?

A

lose expression of CCR7 and differentiate into Tem cells

30
Q

How have effector memory T cells been classified?

A

according to the chemokine receptors typical of Th1; Th17 and Th2 cells

31
Q

what chemokine receptor is typical of Th1 cells?

A

CCR5

32
Q

What chemokine recpetor is typical of Th17 cells?

A

CCR6

33
Q

What chemokine receptor is typical of Th2 cells ?

A

CCR4

34
Q

What experiment suggests taht CD4 cells are needed for a CD8 memory response?

A

mice that dont express MHC II and wild type are infected with listeria epressing OVA, both mice had similar levels of CD8 T cells after 7 days however on re-challenging MHCII deficient mice had no CD8 memory repsonse and much weaker secondary resopnse

35
Q

What interactions are thorught to happen between CD4 and CD8 cells to form memory cells?

A

CD40 and IL-2 receptor

36
Q

What other role apart from in the priming and creation og memory CD8 cells do CD4 cells play?

A

maintenance of the number of CD8 memory T cells

37
Q

What is the effect of memory B and T cells on naive B and T cells?

A

reduce the activation of naive B and T cells on a subsequent encouter to the asame antigen

38
Q

how does the effect of memory B and T ells have on naive B and T cells explain orginal antigenic sin?

A

original antigenic sin: people only make antibodies to the first influenza variant they encounter and not subsequent ones-unless they have none of the same epitopes as the first infection, as the antibodies against hte original virus suppresses the repsonse of naive B cells specific for the new epitopes

39
Q

What does choice between plasma or memory cell fate depend upon?

A

survival ability; specific transcription factors and competition for specific niches

40
Q

What homing molecules do central T cell express?

A

lymph node homing moelcules CCR7 and CD62L

41
Q

What happens over time to the memory pool of Tem and Tcm?

A

gradually changes from Tem to stable and long lived T cm

42
Q

What is the function Trms?

A

present cytotoxic activity and improve pathogen clearance at site of infection

43
Q

What marker is expressed on T cells when they undergone more than 10 rounds of proliferation?

A

KLRG1

44
Q

What is mTOR?

A

a transcription factor regulating complex pathway involved in cell prolfieration, cell growth etc

45
Q

what effect does inhibition of mTOR

A

promotes memory formation and maintenace

46
Q

How do memory cells escape cell death?

A

upregulating anti-apoptoc genes e.g Bcl-2 and Bcl-Xl and receptors for pro-survival cytokines IL7 and IL15

47
Q

What is the acute/chornic decision point?

A

instead of organ damage due to immune response, immune response dampens down and the virus is chronic

Basic Immunology- Module 1 (31 decks)

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