Lecture 10 Development and Survival of Lymphocytes

Question 1

The precursor for T cells develops in the ______ and migrates to the ______

Answer 1

bone marrow; thymus

Question 2

T cells that interact with _____ receive signals for survival. If they interact with ______ they are removed from the repertoire

Answer 2

self MHC;
self antigens

Question 3

Mature T cells migrate to the _______ where they encounter _______ and are activated

Answer 3

peripheral lymphoid organs;
foreign anitgens

Question 4

What do activated T cells do?

Answer 4

proliferate and eliminate infection

Question 5

What are the two key parts of the thymus?

Answer 5

cortex and medulla

Question 6

Which phagocytes are present in the thymus?

Answer 6

macrophages and dendritic cells

Question 7

scid mice are immunocompromised because they can’t ______

Answer 7

do V(D) J

Question 8

nu mice are immunocompromised because they ______

Answer 8

don’t have thymus epithelial cells

Question 9

scid mice that receive ______ from nu mice can make mature T cells

Answer 9

bone marrow stem cells

Question 10

nu mice that receive ______ from scid mice can make mature T cells

Answer 10

thymus graft in kidney

Question 11

____ of cells die in the thymus

Answer 11

98%

Question 12

Double negative (CD3-, 4-, 8-) thymocytes can differentiate into either ____ or _____ thymocytes

Answer 12

CD3+gamma:delta (4-, 8-) OR
CD3+ pT alpha:beta 4+, 8+ (double positive

Question 13

Double negative thymocytes enter the thymus in ______ near the corticomedullary junction and migrate through _______ to the ______

Answer 13

small venules; cortex; medulla

Question 14

As double negative cells proliferate they interact with _______ cells

Answer 14

corticoepithelial

Question 15

the medulla contains only ______ T cells

Answer 15

mature single positive

Question 16

DN1 cells express

Answer 16

CD44 and Kit

Question 17

DN2 cells express

Answer 17

CD44, Kit, CD25

Question 18

Cells are irreversibly committed to becoming Tcells at ___ stage

Answer 18

DN2

Question 19

___ is alpha chain of IL-2

Answer 19

CD25

Question 20

As ____ begin to rearrange beta chain, they become low in ____ and ____

Answer 20

DN2; CD44 and Kit

Question 21

DN3 cells express _____ and _____ and are rearranging ___ chain locus

Answer 21

CD25
low CD44 and Kit
beta

Question 22

the beta chain can pair with ____ in association with CD3 to stop _____ rearrangement

Answer 22

pTalpha
beta

Question 23

pTalpha:beta triggers ______ to stop and loss of _____

Answer 23

cell proliferation; CD25

Question 24

DN4 cells express

Answer 24

negative for CD44 and CD25, they have complete beta chain though

Question 25

Dbeta to J beta rearrangement occurs in

Answer 25

DN2

Question 26

Vbeta to J beta rearrangement occurs in

Answer 26

DN3

Question 27

gamma:delta T cells are found in ____ and ___ sites and lack expression of ____ and ___

Answer 27

epithelial, mucosal; CD4, CD8

Question 28

____ locus is found within alpha

Answer 28

delta

Question 29

rearrangements start ______ and whichever finish first will prevail

Answer 29

independently

Question 30

complete gamma:delta TCR rearrangement will produce strong ___ signal to block production of alpha:beta

Answer 30

Erk

Question 31

_____ is favored because a surrogate molecule can mimic ___ chain to block gamma:delta

Answer 31

alpha:beta; alpha (pTalpha)

Question 32

____ is first to develop day 14-18 and migrates to the skin. It secretes _______

Answer 32

V gamma 5; KGF, inflammatory cytokines and chemokines

Question 33

Next to develop day 16-19 is V gamma __ and it goes to ____. They secrete ___

Answer 33

6; lung, dermis, uterus; IL-17

Question 34

After day 17 of development, Vgamma4 goes to ____ and Vgamma 1,2,7 go to ____

Answer 34

spleen; lymph nodes

Question 35

germline gene process occurs in _______ cell

Answer 35

maturing double negative thymocyte

Question 36

beta chain rearrangement: D to J occurs in ____ cell

Answer 36

CD25+ Cd44low thymocyte rearranging beta-chain genes

Question 37

beta chain: V to DJ occurs in ______ cell

Answer 37

Cd25+ CD44low thymocyte cytoplasmic Beta+

Question 38

surface expression of beta chain with pTalpha results in following processes:

Answer 38

beta rearrangement stops, cell proliferates, CD4/CD8 induction, alpha transcription

Question 39

surface expression of beta chain with pTalpha occurs in ____ cells

Answer 39

CD4-8- -> CD4+8+ surface pTalpha:beta+ CD3low

Question 40

alpha rearrangement: V to J results in the following processes:

Answer 40

surface expression of alpha:beta:CD3 selective events begin

Question 41

pTalpha:beta induce signals that cause phosphorylation and degradation of ____ which halts ______ and induce _____ and ______

Answer 41

Rag2; beta chain rearrangement; cell proliferation and CD4/8 induction

Question 42

pre-TCR is signaled constitutively by ___

Answer 42

Lck

Question 43

pre-TCR triggers expression of _______ phase in DN4 and _____ are repressed

Answer 43

proliferative; RAG1:RAG2

Question 44

a cell with a successfully rearranged _____ chain will give rise to many CD4+8+ progeny that can have unique ____ chains

Answer 44

beta; alpha

Question 45

when the proliferative phase ends, ______ are transcribed again

Answer 45

RAG1 and RAG2

Question 46

When alpha:beta TCR are expressed, _______ can begin

Answer 46

selection by self peptide:self MHC

Question 47

_____ is required for single negative thymocyte

Answer 47

ZAP70

Question 48

alpha chains will undergo rearrangements until _______ or ______ occurs

Answer 48

positive selection OR cell death

Question 49

multiple rearrangements can occur for ____ chains because there are multiple V segments

Answer 49

alpha

Question 50

alpha rearrangement occurs when the thymocyte is CD4/CD8 _______

Answer 50

positive

Question 51

MHC molecules in the _____ limit the repertoire of MHC that TCR can respond to

Answer 51

thymus