T cell ontogeny

Question 1

Beta chain ressembles the (heavy/light) chain

Answer 1

Heavy

VDJ and C

Alpha - VJ and C

Question 2

What complexes are responsible for signal transduction?

Answer 2

CD3 complex and ‘zeta’ chain

Question 3

What allows CD3 and ‘zeta’ chain to transmit signals?

Answer 3

The presence of ITAM (immunoreceptor tyrosine-based activation motif) intracellularly

Tyrosine susceptible to phosphorylation, activation and recruitment of tyrosine kinases and transuce signal.

Question 4

What is the marker of T cells?

Answer 4

CD3

Question 5

Why do old people have immune problems?

Answer 5

Because T cell maturation decreases with age.

Question 6

At what stage are T cells double negatives?

Answer 6

Pro-T cells

Question 7

What chain is subjected to allelic exclusion?

Answer 7

Beta chain

Alpha chian no

Question 8

What T cell has the alpha chain rearranged?

Answer 8

The double positve cells

Question 9

Which selection eliminates unuseful T cells?

Answer 9

Positive selection

Question 10

Where takes place positive selection?

Answer 10

In the cortical thymus

Question 11

How is antigen presentation restricted by MHC molecules?

Answer 11

MHC-1 - CD8
MHC II -CD4

Question 12

Where does negative selection occur?

Answer 12

Medullary region of the thymus.

Question 13

What selection deletes the T cells that can produce an autoimmune response?

Answer 13

Negative selection

Question 14

What transcription factor is in charge of lots of tissue-specific antigens?

Answer 14

AIRE

Question 15

What autoimmune disease is caused by mutation of AIRE?

Answer 15

Autoimmune Polyendocrine Syndrome