Quiz 6

Question 1

__________ at the surface of B cells are secreted by plasma cells to recognize native antigens

Answer 1

antibodies (immunoglobulins)

Question 2

What are the 3 types of B cell populations?

Answer 2

1. B-1
2. B-2 (follicular)
3. marginal-zone B cells

Question 3

Where do B-1 B cells reside?

Answer 3

body cavities

Question 4

What is the primary job of B-1 B cells?

Answer 4

protect gut and lungs

Question 5

Where are B-1 B cells generated?

Answer 5

fetal liver (self renewing)

Question 6

Do B-1 B cells have diversity?

Answer 6

No; generated during fetal development and just self renew (limited VDJ and NO somatic hypermutation and class switching)

Question 7

Are B-1 B cell’s antibodies specific or broad?

Answer 7

broad because they are the first line of defense for cavities (act like PRRs)

Question 8

Do B-1 B cells require T helper for activation?

Answer 8

No (T cell independent)

Question 9

What isotype do B-1 B cells usually produce?

Answer 9

IgM

Question 10

Do B-1 B cells produce memory B cells?

Answer 10

No because they don’t do class switching or somatic hypermutation

Question 11

Where do B-2 B cells reside?

Answer 11

most areas of the body

Question 12

Where are B-2 B cells generated?

Answer 12

bone marrow

Question 13

Are B-2 B cell’s antibodies specific or broad?

Answer 13

broad

Question 14

Do B-2 B cells require T helper for activation?

Answer 14

Yes (T cell dependent)

Question 15

What isotype does B-2 B cells produce?

Answer 15

any of them

Question 16

Do B-2 B cells produce memory B cells?

Answer 16

yes

Question 17

Where do marginal-zone B cells reside?

Answer 17

spleen

Question 18

What is the purpose of marginal-zone B cells?

Answer 18

protect against blood borne pathogens

Question 19

What isotype does marginal-zone B cells produce?

Answer 19

IgM (can do IgG)

Question 20

Do B cells stay in primary tissues until development is complete?

Answer 20

No they leave and finish development in spleen where they can interact with T cells

Question 21

What is the commitment signal for B cells?

Answer 21

IL-7

Question 22

Bone marrow stromal cells express _______ and cells destined to become a B cell expresses ______

Answer 22

IL-7

IL-7R

Question 23

What happens during Early Pro stage of B cell development?

Answer 23

heavy chain VDJ recombination
DJ join

Question 24

What happens during Late Pro stage of B cell development?

Answer 24

V joins DJ
checkpoint got productive heavy chain

Question 25

What happens during Pre-B stage of B cell development?

Answer 25

light chain VJ recombination checkpoint for light chain

Question 26

What happens during immature B stage of B cell development?

Answer 26

negative selection receptor editing exit bone marrow for spleen

Question 27

What happens during T1 stage of B cell development?

Answer 27

negative selection peripheral tolerance

Question 28

What happens during T2 stage of B cell development?

Answer 28

positive selection

Question 29

What does the B cells surrogate light chain contain that tests if the heavy chain works?

Answer 29

VpreB and gamma 5

Question 30

What does VpreB mimic?

Answer 30

variable region of the light chain

Question 31

What does gamma5 mimic?

Answer 31

constant region of the light chain

Question 32

During the heavy chain checkpoint, the heavy chain forms a complex with ____ and _____ to test for the ability to form the Pre-B cell receptor

Answer 32

Ig alpha Ig beta

Question 33

What happens to a large pre-B cell?

Answer 33

allelic exclusion of heavy chain

Question 34

What happens to small pre-B cells?

Answer 34

light chain recombination

Question 35

What are the 2 loci of small pre-B cells?

Answer 35

kappa and lambda

Question 36

If one light chain loci of BCR cannot make a functional light chain what happens to the other light chain loci?

Answer 36

it gets a chance to rearrange

Question 37

If the heavy and light chain both successfully rearrange, what is the B cell called now?

Answer 37

immature B cell

Question 38

What are the stages of a B cell?

Answer 38

1. early pro-B cell 2. late pro-B cell 3. large pre-B cell 4. small pre-B cell 5. immature B cell

Question 39

Immature B cells in the bone marrow that recognize self-antigen have three fates...

Answer 39

1. clonal deletion (apoptosis) 2. receptor editing (second try) 3. anergy

Question 40

What are multivalent antigens?

Answer 40

molecules with more than one identical antigen receptor results in cross linking of BCRs

Question 41

What are monovalent antigens?

Answer 41

molecules with a single antigen receptor no cross linking of BCR

Question 42

Where does the first negative selection occur?

Answer 42

Bone marrow

Question 43

Is negative selection in B cells as strict as T cells?

Answer 43

No, they don't have AIRE because they use other T cells instead

Question 44

What are B cells called that continue thier development in the spleen?

Answer 44

Transnational B cells

Question 45

What happens during transitional 1 B cells?

Answer 45

another round of negative selection

Question 46

What does T1 B cells express lower during negative selecgtion?

Answer 46

BAFF

Question 47

What happens during transitional 2 B cells?

Answer 47

another positive selection

Question 48

_____B cells need BAFF but ____B cells dont

Answer 48

B-2 B-1

Question 49

What do marginal B cells attack?

Answer 49

blood born pathogens

Question 50

What is the first step of B cell activation?

Answer 50

cross linking BCR that signals ITAM cascade

Question 51

What 3 things are B cell corecptors made of?

Answer 51

CR2 CD19 CD81

Question 52

In B cell activation, what is the signal that starts the 3 signaling pathways?

Answer 52

Syk

Question 53

Do T-2 independent B cells require a secondary signal?

Answer 53

no

Question 54

Do T-1 or T-2 independent B cells do excessive crosslinking of BCR?

Answer 54

TI-2

Question 55

What 2 signals does T dependent B cells require?

Answer 55

BCR-C3b CD-40