Lecture 13 - B cells and their Response to Antigen

Question 1

B cells differentiate to

Answer 1

plasma cells

Question 2

Plasma cells secrete

Answer 2

antibodies

Question 3

Antibodies are also called ____ and are ____ with a common basic structure

Answer 3

Ig, glycoproteins

Question 4

How many copies of identical BCRs does a B cell have

Answer 4

300,000

Question 5

How many epitopes can one B cell recognize

Answer 5

1

Question 6

B cell spends its life how

Answer 6

in search of its antigen

Question 7

What happens if a B cell doesn’t encounter its antigen in 3-4 months

Answer 7

it will die

Question 8

What happens if a B cell encounters its antigen

Answer 8

activated and expands clonally, some clones differentiate into plasma cells and some become long lived memory cells

Question 9

What cells secrete antibodies

Answer 9

plasma cells

Question 10

What do cytotoxic T cells recognize

Answer 10

processed epitopes by MHC I

Question 11

What do helper T cells recognize

Answer 11

processed epitopes by MHC II

Question 12

What do B cells recognize

Answer 12

native epitopes

Question 13

What form the antigen binding site on the B cell

Answer 13

CDRs (complementariliy determining regions)

Question 14

In addition to coming into contact with its antigen, what else can help activate a B cell

Answer 14

cytokines, stimulation of PRRs, Helper T cell contact, complement

Question 15

How do B cells and Th cells interact

Answer 15

CD40 (B cell) and CD154 (Th cell) mediated dialog

Question 16

How is the secondary antibody response different from primary

Answer 16

stronger and faster because there are memory cells, affinity maturation

Question 17

Differentiate between T-dependent and T-independent antibody responses

Answer 17

T-dep: isotope switched, high-affinity antibodies, memory B cells, long-lived plasma cells
T-indep: mainly IgM, low affinity antibodies; short-lived plasma cells, no class switch, no memory