Putting Lymphoid Cell Receptors Together

For Immunology Chapter 7 Day 3

1. Discuss the purpose of the VpreB, 5λ, and pre-Tα proteins.
2. There are two points in the flow chart of figure 7-11 where a B cell may choose to die. What has to happen to get these two points?  Why does the B cell get more “chances to live” when it is attempting to produce its light chain?  (The last question should acknowledge “receptor editing” as well as productive gene rearrangement.)
3. In what state of maturation would you expect a B cell to produce mostly membrane-bound IgM? Secreted IgM? Membrane bound IgD?  Secreted IgD?
4. Discovery of the murine TCRβ gene started with a technique called subtractive hybridization. How does this technique work?
5. Allelic exclusion is not absolute in T cells. Why would it be unlikely to have a mature T cell with two unique TCRs?
6. How were γδ T cells discovered?