B cells and humoral immunity

Question 1

B lymphocytes are responsible for what type of adaptive immunity

Answer 1

humoral immunity (antibodies)

Question 2

origin of “B” in name B lymphocytes

Answer 2

originally from “bursa of Fabriciuis,” but can think of bone marrow because in humans develop here

Question 3

B lymphocytes can differentiate into

Answer 3

plasma cells, which produce antibodies

Question 4

antigen naive B lymphocytes have which antibodies

Answer 4

IgM and IgD

Question 5

mature B cell

Answer 5

developed in bone marrow and released into the bloodstream, but still “antigen-naive” until it encounters antigen
express IgM and IgD antibodies on cell surface

Question 6

affinity maturation

Answer 6

the longer an immune response goes on, the higher the affinity the antibody has for the antigen
occurs in secondary immune response

Question 7

B lymphocyte maturation

Answer 7

stem cell
pro-B
pre-B
immature B
mature B

Question 8

most important stage in development of a B cell

Answer 8

immature B cell stage
at this stage, cell gets rid of self-reactive B lymphocytes that react to cell’s own tissue
cells that are not deleted at this stage go on to become a mature B cell, characterized by IgM and IgD on surface
if activated, mature B cells become plasma cells

Question 9

B cell differentiation

Answer 9

mature B lymphocytes can:
become plasma cells (produce antibodies)
undergo isotype switching
undergo affinity maturation
become memory B cells

Question 10

plasma cells

Answer 10

secrete one antibody isotype
found in lymphoid organs and bone marrow
lifespan: a few days (some liver longer in bone marrow)
morphology: elongated cell, eccentric nucleus, perinuclear halo