1) Explain the development of an early thymocytes (T cell)?
2) At what stages of the development dies TCR gene segment recombination occur?
What does it yield after this rearrangement?
3) What is flow cytometry used for? how does it work? DP what do u see?
4) As the cell goes from ProTCR to PreTCR what types of changes u c?
5) How does Pre T cell proliferation increases diversity in T cell?
6) If a “α” chain does not rearrange properly what happen next?
7) Explain positive and negative selection in DP (80%) cells in thymus.
8) What cells are involved in doing the + and – selection? What are the three
outcomes when a Thymocytes binds to these cells?
9) Explain how the cTEC presents peptides on MHC?
10)What is MHC restriction? ( ask professor about the experiment)
11) how does the developing T cells know whether to express CD4 or CD8 T cells?
(Explains the three models)
12)what does central tolerance mean?
13)Negative selection: purpose? What stage of development does it occur? Requires
interaction with what? Is peptide highly involved?
14) Wher do the peptides for negative selection come from?
15)What is AIRE? What happens if defective?
16) What control the final maturation of the T cell?
17)When T cells leave the thymus what are they called now?
18)When H2k mice are transplanted with H2d (ask prof about this experiment)
cells, you get an allogeneic response. Why is this Even though H2k cells have
never seen H2d cells before? 1) form in Bome marrow▯migrate to the thymus through the blood ▯ DP▯Positive and
negative selection occurs to leave only SP (CD4 or CD8)▯final screening removes
the auto reactive▯release into blood.
2) DN is the stage in which the TCR beta (B) gene recombination occurs at this
moment it will become T cell but It leads to two different types of cells either αβ
or γδ T cell. If the αβ occurs, then α chain begins rearranging.
3) Helps determine the cell surface proteins (markers) by using an antibody that
binds to that particular markers and glows. Have 4 boxes. Bottom left▯no markers
present. Top rights▯both markers present. Bottom right ▯ only marker on the
horizontal is present. Top left ▯ on the marker on the vertical is present. Thus on
DP T cell in the thymus you will see top right (as both the CD4 and CD8 are both
4) ProT cell▯ β chain begins rearrangement and a functional VDJ rearrangement
occurs (no alpha yet)▯the beta chain protein is formed but is not put on the surface
yet need Alpha chain. No Alpha chain yet so instead we have PreTα = surrogate
for real TCR α chain and it promotes receptors dimerization . The both of these
come together we get many signals (through tyrosine phosphorylation) such as the
real α chain rearrangement AND stimulates CD4 and CD8 expression (DP cell
now) AND stops addition B rearrangement (allelic exclusion) And stimulates
5) Progeny cells will pair the same “