Immunology Test 2 - Set 2

Front 1

Before a mature naïve Bcell must ? – before they have made contact w/ its sp. An?

Back 1

1) Periodically pause in a primary follicle in order to survive and continue its recirculation

Front 2

within the follicle the mature naïve Bcell ?

Back 2

1) receives survival signals
a) may come from follicular dendritic cells

Front 3

how many B cells leave the bone Marrow daily?

Back 3

1) 30 billion > circulating naïve B cells

Front 4

what does the B cells pause in the follicular sites cause?

Back 4

1) Continual competition b/t circ naïve B cells passage thru limited # of follicular sites
a) The majority of mature, naïve B cells die after only a few days in peripheral circulation.

Front 5

Mature Naive B cells compete?

Back 5

for access to lymphoid follicles.

Front 6

After maturing in the bone marrow where to B cells migrate to?

Back 6

1) In the blood to lymph nodes and other 2nd tissues

Front 7

how do B cells enter the lymph node?

Back 7

1) leave the blood and enter the cortex
a) thru the walls of HEV

Front 8

HEV?

Back 8

1) Specialized high endothelial venules

Front 9

If B cells do not encounter their specific antigen?

Back 9

1) It passes thru the prim follicles and leave the node
a) Thru efferent lymph>blood.

Front 10

B cells encounter with An, leads to?

Back 10

1) Differentiation of activated Bcells into
a) Plasma cells
b) Memory B cells

Front 11

plasma cells?

Back 11

1) secrete antibody

Front 12

Antibody secretion is effected by?

Back 12

1) a change in the processing of the H-chain mRNA
a) Leads to the synthesis of secreted form of Ig rather than memrane bound form

Front 13

Activated B cell?

Back 13

1) Migrates > 2nd lymphoid follicle (aka germ center
a) To become centroblasts
(i) Which mature into centrocytes

Front 14

secondary lymphoid follicle?

Back 14

1) contains germinal center
2) activated B cells b/c centroblasts here

Front 15

Centroblasts?

Back 15

1) Large proliferating lymphoblasts
a) Mature into centrocytes

Front 16

centrocytes?

Back 16

1) non-dividing B cells
2) which have undergone isotype switching and somatic hypermutation

Front 17

Germinal center B cells develop into?

Back 17

1) Memory B cells

Front 18

Memory B cells?

Back 18

1) Posess high-affinity, isotype-switched antigen receptors

Front 19

production of mem cells after successful antigen encounter establishes?

Back 19

1) Antigen specificities of proven usefulness permanently in the B cell repertoire

Front 20

what are some properties of mem B cells?

Back 20

1) Persist for long periods of time
2) During recirculation require only intermittent stim. From follicular env.
3) More easily activated on An encounter than vaive B cells
4) Secondary immune response

Front 21

Secondary immune response?

Back 21

1) Due to rapid active, and differentiation ointo plasma cells on subsequent encounter w/ An.
2) Develops more quickly than prim
3) Stronger than prim.

Front 22

B cells encountering An in 2nd lymph tiss. Form and undergo?

Back 22

1) Germinal centers
2) Differentiation into plasma cells

Front 23

a B cell enters the lymph node and encounters An where?

Back 23

1) In the lymph node cortex

Front 24

what is the B cell activated by?

Back 24

1) CD4 helper T cells
a) In T cell area

Front 25

encounter with CD4 T cells form? Go where?

Back 25

1) primary focus of dividing cells
a) medullary cords
b) primary follicle

Front 26

B cells that migrate directly to the medullary cord?

Back 26

1) Differentiate into Ab secreting plasma cells

Front 27

cells that migrate to the primary follicle?

Back 27

1) Form germinal centers
a) Where the continure to divide and differentiate

Front 28

activated B cells?

Back 28

1) Migrate from the germinal center to
a) the medulla of lymph node
b) bone marrow
(i) to complete diff. into plasma cells

Front 29

Different types of B cell tumors?

Back 29

reflect B cells at diff. stages of development

Front 30

B cell rumore arise from?

Back 30

both B1 and B2 lineages
and at diff stages of maturation and differentiation.

Front 31

in a b cell tumor - every cell?

Back 31

1) Has identical Ig-gene rearrangement
a) = proof of their derivation from same cell.

Front 32

Tumors?

Back 32

1) Retain characteristics of the cell type from which they arose

Front 33

follicular center cell lymphoma?

Back 33

1) tumors derived from mature, naïve B cells
a) grow in the follicles of lymph nodes

Front 34

myelomas?

Back 34

1) plasma-cell tumors
a) propagate in bone marrow

Front 35

Hodkin’s disease?

Back 35

1) One of the 1st tumors to b successfully treated by radiotatapy
2) Origin = germinal center B cell
3) Result = somatic mutation
a) No longer have An receptor.