Lecture 12

Question 1

Before birth B cells precursors commit in?

Answer 1

liver, after in bone marrow

Question 2

mature further in

Answer 2

spleen, when expressing IgM

Question 3

follicular B cells express?

Answer 3

IgM and IgD, populated all peripheral lymphoid organs

Question 4

earliest cell commited to B

Answer 4

pro B, no Ig

-Rag1 and 2 first expressed later for Heavy chains

Question 5

TDT most abundant

Answer 5

on pro B stage When VDJ recombination occurs at Ig H locus

Question 6

cecreases befreo L chain gene VJ recombination is complete

Answer 6

TdT

Question 7

most abundant in H chain

Answer 7

junctional diversity

Question 8

primary transcript occurs

Answer 8

undergoes splicing introns are removed exons joined.

Question 9

pre BCR composed of

Answer 9

u IgH.. invariant surrogate IgL

Question 10

surrogan IgL

Answer 10

V pre B protein and lambda 5 protein… turn into k and lambda chain

Question 11

covalently attached to the u IgH chaing by disulfide bond

Answer 11

lambda5

Question 12

What singls show up as n B mature B cells

Answer 12

alpha and beta signal transudcers

Question 13

rearrangment of IgH locus

Answer 13

at the pro B cell stage… gives rise to u Ig chain if successful

Question 14

first check point for B cells

Answer 14

expression of pre BCR

Question 15

downstream signal responsible for proliferation survival and maturation of pre BCR

Answer 15

BTK bruton’s tyrosine kinase

Question 16

mutation in BTK

Answer 16

agammaglobulineamia XLA… falure of b cell maturation

Question 17

light chain isotope exclusion

Answer 17

only one type can present

Question 18

BCR provides Ag independent toxic signals that?

Answer 18

shuttoff the RAG gene expression that prevent further Ig rearrangment

Question 19

most B cells from fetal liver or stem cell become

Answer 19

B1

Question 20

bone marrow precursors after brith give rise to

Answer 20

B2

Question 21

B1 cells have?

Answer 21

Igm, CD5,

Question 22

folicular B2 cells have

Answer 22

Igm and IgD recirculating lymphocytes

Question 23

Marnial zone B cells have

Answer 23

Igm and CD/21/CR2, abundant in sleepn and Lns

Question 24

B1 B’s are

Answer 24

self renewing, produce natural Abs involved in self defense

Question 25

folicular B2 cells are the only ones to??

Answer 25

devlop into long lived plasma cells or memory B cells | -must be replenished in bone marrow

Question 26

MZ B cells

Answer 26

repsond to blood borne ags

Question 27

MZ B's are?:

Answer 27

independent of T helper cells

Question 28

MZ and B1

Answer 28

self renewing

Question 29

B1B pleural and peritoneal cavites

Answer 29

most of serum IgM in early phases of infection

Question 30

what is not expressed in fetal liver?

Answer 30

TdT, causing limmited BCR diversity in B1 cells

Question 31

B1 sponateoulsy secrete IgM for?

Answer 31

microbial polysacchariedes and lipids and oxidized lipids | -natural antibodies

Question 32

How are follicular B cells expressed?

Answer 32

long primary RNA then, alternative RNA splicing

Question 33

MZ B cells

Answer 33

Marginal sinus of sleen | -respond to polysaccharid Ags and genreate natural Abs

Question 34

MZ B cells turn into

Answer 34

short lived IgM secreting plamsa cell. dealing with blood borne microbes

Question 35

thymic environment

Answer 35

required for proliferiation and matruation of thymocytes

Question 36

DiGeorge snydrome

Answer 36

immulogic deficency associated with lack of thymus

Question 37

developing T cells in the thymus

Answer 37

thymocytes- mostly occurs in the cortex... then enter medulla and exit the thymus through circultion

Question 38

cortical epithelial cells

Answer 38

essential for meshwork of thymocytes maturation

Question 39

epithelia cells in medulla

Answer 39

role of APCs for negative selection

Question 40

macrophages present in what of thymus

Answer 40

medulla

Question 41

What causes entry to thymus

Answer 41

CCL25 recognizes CCR9 on precursors

Question 42

CCL21 and CCL19 recognized?

Answer 42

thymocytes via CCR7 and guide movement from cortext to medulla

Question 43

proliferation of thymocyes

Answer 43

IL7

Question 44

cortical thymocytes do not express?

Answer 44

TCR CD3, zeta chains, cd4 or cd 8 | -these are considered to be double negative state and pro T

Question 45

Rag 1 and 2 are first expressed in ?

Answer 45

double negative stage

Question 46

The Dj rearrangement of what is first?

Answer 46

the beta locus

Question 47

VDJ rearrangement occurs in what stage?

Answer 47

pro-- pre t

Question 48

What controls TCR alpha signal recombination

Answer 48

a second wave of rag

Question 49

What are the only cells that mediate positive slection of TCR and how?

Answer 49

by displaying slef peptides bound to I and ii mhc molecules ... cortical epithelial cells

Question 50

go from double positive to single positive

Answer 50

depends on what mhc class they recognize as to if they become cd4 or cd8

Question 51

what activate Runx3 that maintain CD8 T cell phenotype?

Answer 51

weak signals

Question 52

What causes CD4 fate?

Answer 52

GATA 3

Question 53

What is the proapoptotic protein?

Answer 53

BIM that plays a cruicial role in the induction of mitochondrial leakiness Ca and apoptosis

Question 54

DC and Mo in the medulla?

Answer 54

are APCs that mediate negative selection

Question 55

regulatory T cells

Answer 55

develop from high affitity to self and act as autoimmune reactions

Question 56

lambda beta cells are?

Answer 56

limited