Lecture 4 - B and T cell development

Question 1

in B cell development, in which reaction does most cell division occur?

Answer 1

germinal centre reaction

Question 2

the germinal centre reaction is related to what type of immune response? primary or secondary?

Answer 2

secondary

Question 3

where do B cells originate from?

Answer 3

haematopoietic stem cells in the bone marrow

Question 4

which transcription factor do B cells express?

Answer 4

PAX 5

Question 5

what is the correct order of B cell development?

a) L chains rearrange
b) L chain expression stopped
c) H chain rearranges, expressed with surrogate L chain
d) pre-BCR turns off RAG 1 and 2
e) cell division
f) RAG 1 and 2 turned on again

Answer 5

c, d, e, b, f, a

Question 6

immature B cells express which Ig only?

Answer 6

IgM

Question 7

immature B cells that bind multivalent self antigen undergo one of two processes. what are they?

Answer 7

either clonal deletion or receptor editing

Question 8

immature B cells that bind soluble self antigen become what?

Answer 8

anergic

Question 9

True or false: B cells undergo positive and negative selection?

Answer 9

false, this is what T cells undergo

Question 10

if cells don’t express PAX5, they leave the bone marrow and go to the…… to become ……cells

Answer 10

thymus

T cells

Question 11

gamma delta T cell receptors are found in which tissues?

Answer 11

epithelial

Question 12

alpha beta T cell receptors bind with self…. molecules in the thymus and undergo ……. selection

Answer 12

MHC

positive

Question 13

Regarding T cell development, thymocytes, in the thymus, express which receptor?

what markers do they acquire? (hint: what are the types of T cell)

Answer 13

t cell receptor

they acquire CD3, CD4 or CD8 markers

Question 14

the lobules of the thymus are divided into what two things?

Answer 14

cortex and medulla

Question 15

where are pro-thymocytes found within the thymus? which section?

Answer 15

cortex

Question 16

which genes are rearranged first in T cells? which are rearranged second?

(TCR beta or TCR alpha)

Answer 16

TCR beta first

TCR alpha second

Question 17

the CD3 TCR complex has which 4 chains, one being a dimer?

which chain is the dimer?

Answer 17

gamma, delta, epsilon, zeta

zeta chain is the dimer

Question 18

where does the CD3 TCR complex submit the signal to within the T cell, following MHC recognition?

Answer 18

to the nucleus

Question 19

which CD markers do gamma-delta T cells NOT express?

Answer 19

CD4, CD8

Question 20

where in the thymus, does positive selection occur?

Answer 20

in cortex

Question 21

where do positively selected T cells move to in the thymus?

Answer 21

medulla

Question 22

what do positively selected T cells recognise?

Answer 22

self-MHC molecules

Question 23

what happens to T cells which can’t recognise self MHC molecules?

Answer 23

die/apoptosis

Question 24

where does negative selection of T cells occur in the thymus?

Answer 24

medulla, following positive selection

Question 25

in the negative selection of T cells, T cells which recognise MHC on which cells with what affinity are clonally deleted?

Answer 25

on thymic dendritic cells

with HIGHEST affinity

Question 26

in T cell development, the production of T cells with which property is the goal?

Answer 26

the production of T cells with low affinity for self peptide/self MHC

Question 27

what could T cells with low affinity for self MHC induce in a human individual?

Answer 27

autoimmunity