Questions for Generation of Diversity

1. Which of the following gene sequences is/are

1. germline H?
2. germline L?
3. a recombined heavy chain sequence?
4. a recombined light chain sequence?
5. present in a cell that is making IgM and IgD?
6. present in a cell that has switched to making IgG?
7. present in a macrophage?
8. present in a T cell?

A  5'  V1 V2 V3 V4 V5...Vn J1 J2 J3 J4 J5 intron Cκ 3'

B  5' V1 V2 V3 V4 V5 D3 J2 J3 J4 J5  intron Cμ Cδ Cγ3 Cγ1 Cα1 Cγ2 Cγ4 Cε Cα2 3'

C  5'  V1 V2  V3 V4 D2 J4 J5  intron  Cγ1 Cα1 Cγ2 Cγ4 Cε Cα2 3'

D  5' V1 V2 V3 V4 V5...Vn D1 D2 D3 D4 D5...Dn J1 J2 J3 J4 J5 intron Cμ Cδ Cγ3 Cγ1 Cα1 Cγ2 Cγ4 Cε Cα2 3'

E  5'  V1 V2  V3 J2 J3 J4 J5 intron Cκ 3'

F  5' V1 V2 V3 V4 V5...Vn D1 D2 J3 J4 J5 intron Cμ Cδ Cγ3 Cγ1 Cα1 Cγ2 Cγ4 Cε Cα2 3'

2. What are 3 factors in somatic recombination that increase the diversity of antibodies?

3. What limits diversity?