B-Cell Development

Question 1

How many distinct antigen receptors can B cells generate?

Answer 1

1x10^11

Question 2

How many distinct genes are present in the human genome?

Answer 2

25000

Question 3

What is the difference between the Ig heavy chain locus and the Ig light chain loci?

Answer 3

Heavy chain = V, D, and J gene segements
Light chain = No J gene segment

Question 4

What two light chain loci are there?

Answer 4

Kappa and lamda

Question 5

What are the two mechanisms of diversity for antigen receptors?

Answer 5

Combinatorial diversity and junctional diversity

Question 6

What is combinatorial diversity?

Answer 6

The number of possible VDJ combinations

Question 7

What is junctional diversity?

Answer 7

Total potential repertoire with junctional diversity

Question 8

What are memory lymphocytes?

Answer 8

Produced from naive lymphocytes as a result of antigen exposure
Persist for years in a quiescent state
Rapidly reactivated by repeat exposure to an antigen and mediate faster, more potent immune responses

Question 9

Are primary or secondary responses better at handling infections?

Answer 9

Secondary
Take 1-3 days, larger peak response, more IgG and IgA and IgE and a higher average affinity

Question 10

Does class switching affect the variable region?

Answer 10

No
The antibody retains antigen specificity but a new constant region means it has new effector functions