8: Antibody Diversity

Question 1

Plasma cells

Answer 1

terminally differentiated and activated B cells that secrete antibodies

Question 2

What cells in bone marrow stimulate B cell differentiation?

Answer 2

stromal cells

Question 3

What is antibody gene rearrangement called?

Answer 3

V(D)J recombination

Question 4

V genes

Answer 4

variable

Question 5

J genes

Answer 5

joining

Question 6

D genes

Answer 6

diversity

Question 7

What 2 genes recombine first?

Answer 7

D and J

Question 8

What region is not present in light chains?

Answer 8

D

Question 9

Recombination activating genes (RAG)

Answer 9

drives gene rearrangement

Question 10

Multiple germline gene exons

Answer 10

both heavy and light chains may be encoded by multiple variable region DNA segments that are spliced together to form the variable exon region

Question 11

H and L chain combinations

Answer 11

the antigen binding site is formed by the interaction of both chains, and any given H chain can dimerized with any given L chain

Question 12

Imprecise joining of segments

Answer 12

during somatic rearrangement, the gene segments for a variable region can be spliced together using any of several nucleotides

Question 13

Random insertion of bases

Answer 13

during splicing, nucleotide bases can be randomly inserted into the splice junction, changing the codon frame

Question 14

Somatic hypermutation

Answer 14

areas within the variable regions are subject to germline base substitutions during cell division

Question 15

What is the only diversity mechanism that occurs after a B cell encounters its specific antigen?

Answer 15

somatic hypermutation

Question 16

Receptor editing

Answer 16

when an antibody is created that binds to self antigens, the B cell may try another recombination

Question 17

Allelic exclusion

Answer 17

successful rearrangement of the antibody gene DNA is a random event which occurs only on one chromosome for each light or heavy chain genes

Question 18

What does allelic exclusion assure?

Answer 18

that each individual B cell generates only a single antibody molecule

Question 19

Which chain rearranges first?

Answer 19

heavy