Ingham-3: B Cell Development I

Question 1

2 examples of primary lymphoid organs

Answer 1

bone marrow and thymus

Question 2

Plasma cell

Answer 2

B cells that secrete Ab

Question 3

Memory B cells

Answer 3

stay after infection just in case pathogen comes back again

Question 4

stages of B cell development (x7)

Answer 4

HSC –> CLP –> pro-B –> pre-B –> immature B –> transitional B –> mature B

Question 5

What stages of B cell development occur in bone marrow?

Answer 5

HSC –> Immature B cell

Question 6

What stages of B cell development occur in secondary lymphoid organs?

Answer 6

transitional to mature B cell

Question 7

What stage of B cells is committed into becoming a B cell?

Answer 7

pro-B cell

Question 8

What earliest stage of B cell expresses IgM on cell surface?

Answer 8

immature B cell

Question 9

What stage of B cell expresses highest amounts of IgD?

Answer 9

mature B cell

Question 10

Function of Pax5

Answer 10

turns off expression of Notch

Question 11

What is Notch?

Answer 11

T cell lineage transcription factor

Question 12

When do Rag-1/2 genes turn on?

Answer 12

Pro-B cell stage

Question 13

What is rearranged first in the heavy chain?

Answer 13

D and J

Question 14

What is important in getting past the pro-B cell stage?

Answer 14

active Rag-1/2

Question 15

What phenotype is expressed when an organism lacks Rag genes?

Answer 15

SCID (severe combined immunodeficiency disorder)

Question 16

What do transgenic genes mean?

Answer 16

addition of DNA (synthetic)

Question 17

What does knock out genes mean?

Answer 17

alter a gene so it cannot make functional protein or mRNA product

Question 18

What do knock in genes mean?

Answer 18

replace a functional gene with a mutated version of it

Question 19

What characterizes the development of a pre-B cell?

Answer 19

rearrangement of heavy chain

Question 20

2 stages of pre-B cell

Answer 20

• early/large

- late/small

Question 21

What is IgH?

Answer 21

heavy chain gene

Question 22

What makes IgH helpful in promoting DNA transcription?

Answer 22

• has promoters upstream of V segment

Question 23

Function of promoters in IgH?

Answer 23

recruits RNAPII to start transcription

Question 24

Where are enhancers located in IgH locus?

Answer 24

between constant and variable regions

Question 25

What is the B cell specific TF that binds IgH promoter?

Answer 25

Oct-2

Question 26

Surrogate light chains are composed of?

Answer 26

• VpreB

- lambda5

Question 27

Do all pre-B cells express surrogate light chains?

Answer 27

yes

Question 28

What is VreB similar to?

Answer 28

VL

Question 29

What is lambda5 similar to?

Answer 29

CL

Question 30

What structure of the surrogate light chain allows pre-BCRs to self-aggregate?

Answer 30

VpreB has extra C-terminal acidic residues and lambda5 has basic N residues

Question 31

What is the mutated gene in people who have X-linked agammaglobulinemia (XLA)?

Answer 31

btk gene