BCR and B cell Devo

Question 1

The arm of the Adaptive immune system that fnxs to combat extracellular pathagens and toxins

Answer 1

Humoral Immunity

Question 2

The humoral immune response are activated by and recognize?

Answer 2

Proteins, polysaccs, lipids, small chemicals

Question 3

How do antibodies fnx?

Answer 3

Block microbes or their toxins from binding to and infecting host cells. Also limit infection of intracellular pathogens

Question 4

Defects here result in increased suspecitbility to viral, bacterial and parasitic infection

Answer 4

Antibody production

Question 5

Antibodies recognize _________ alone and T cells need presentation by_______

Answer 5

Antigen

APC

Question 6

What make up TCR and BCR complexes?

Answer 6

antigen receptors and attached signaling proteins

Question 7

Signally requires binding of ______

Answer 7

two or more membrane Ig’s (BCR)

Question 8

What forms of antigens to antibodies recognize?

Answer 8

Macromoleucles like proteins. polysachs, lipids, nucleic acids, conformational and linear epitopes

Question 9

Where do AntiB’s get diversity?

Answer 9

each clone has unique specificty and potential for over 1000000000 specificities

Question 10

What mediates signal fnx of antibodies?

Answer 10

Ig alpha and Ig Betta associated w/ membrane Ig

Question 11

Effector regions are mediated by?

Answer 11

Constant regions of secreated Ig

Question 12

What restricts TCR recognition?

Answer 12

MHC I or II

Question 13

What mades up antiG binding regions of Ig’s?

Answer 13

3 CDRs in Vh and three CDRs in VL

Question 14

What is special about constant regions of BCRs?

Answer 14

They can change: called class switching and is done in the Heavy Chain; will switch from membrane bound to secreated form

Question 15

If affinity of antiG binding strong or weak for Ig?

Does it change?

Answer 15

STRONG… more neg KD is stronger it is

Has stronger initial affinity and increases strength w/ response

Question 16

Does TCR affinity get stronger/weaker/fixed?

Answer 16

fixed

Question 17

Which receptor only recognizes antiG in context of peptide and MHC?

Answer 17

TCR

Question 18

Which receptor can recognize numerous chem structures: proteins/lipids, ect?

Answer 18

BCR

Question 19

What kind of forms do BCR come in?

Answer 19

Bound and secreated

Question 20

Where are TCR located?

Answer 20

membrane localized

Question 21

These receptors are made of heavy and light chain proteins?

Answer 21

BCR’s

Question 22

These guys are made of alpha and beta chains?

Answer 22

TCR

Question 23

During Early lymphocyte devo: you can become either B cells or T cells:
B cells will express________
T cells wil express_________

Answer 23

heavy chain protein expression

TRC beta chain protein expression

Question 24

What is our mitogenic signal for devo’in lymphocytes (both B and T) to proliferate?

Answer 24

IL7

Question 25

IL7 is made by?

Answer 25

bone marrow stromal cells

Question 26

After a Pro B cell is exposed to IL-7 and proliferates, B cell will express what?

Answer 26

one chain of antiG receptor: the Ig heavy chain and is now a Pre-B cell

Question 27

After 2nd exposture to IL-7 what does the B cell do?

Answer 27

Expresses complete antiG receptor, proliferates and has weak antiG recognition

Question 28

What are the three gene segments that recombine during cellular differentiation and maturation of B cells?

Answer 28

V(variable) D(Diversity) and J(joining)

Question 29

What is our first recombination event?

Answer 29

heavy chain D and J exons to DJ

Question 30

What is our second recombination event?

Answer 30

V combines with DJ

Question 31

VDJ recomibination of Ig H C______ region gene segment (first Constant region)

Answer 31

Mew

Question 32

What makes up a heavy chain transcript and where does it need to be expressed to get past first checkpoint?

Answer 32

VDJC and needs to be intact on cell surface with a surrogate light chain

Question 33

How is light chain made?

Answer 33

V and J come together then join light Cmew segment to make up transrcript for Ig Light chain

Question 34

What is required at our second checkpoint?

Answer 34

Have recombinded H chain and C mew which is now collectively makes up Ig M

Question 35

What is our B cell called at second checkpoint?

Answer 35

Immature B cell

Question 36

Order of B cell maturity

Answer 36

Stem cell–> Pro B–> Pre-B–> Immature B–> Naive Mature B

Question 37

Where do Mature B cells go?

Answer 37

To peripheral immune tissues such as spleen or lymph nodes. Haveen’t met their antiG yet

Question 38

What Ig’s do a mature B cell express?

Answer 38

Ig G and Ig M

Question 39

What confers antiG specificity on an antiBody

Answer 39

the dimeric protein of the BCR

Question 40

Difference btwn T and B cell binding site it?

Answer 40

T cell has one binding site or groove

B cell has 2 identical binding sites that see same epitope/antiG

Question 41

What is Fab region of antiB?

Answer 41

its our variable region that recongizes diverse antiG

made of light and heavy chain

Question 42

What makes up stalk of antiB

Answer 42

Fc region = constant region, also has complement binding sites

Question 43

how many different constant regions are there in B cells?

Answer 43

Up to 9 dif constant regions

Question 44

Where is D region expressed?

Answer 44

only inIg Heavy chain

Question 45

In the Junctional region, which enZ adds NT?

Answer 45

TdT enZ

Question 46

What are the two mechanisms for antiG Diversity?

Answer 46

Combinatorial and Junctional

Question 47

method that results in variation amongst possible V-D-J and VJ exon combinations

Answer 47

Combinatoral

Question 48

method that involves removal of NTs, adds NT via TdT and has strand repair during recombination process

Answer 48

Junctional

Question 49

Each variable region of Ig H and Ig L have 3 regions of HYPERavailability known as:

Answer 49

CDR: CD1, CD2, CD3