T-cell development

Question 1

TCR has a _____ and a _____ region

Answer 1

TCR has a variable and a constant region

Question 2

Most common TCRs are composed of an ____ and _____ chain. Less common ones have ____ and ____ chains.

Answer 2

Most common TCRs are composed of an alpha and beta chain. Less common ones have gamma and delta chains.

Question 3

Unlike Ig’s, in TCRs:

Answer 3

1) Tere is no soluble form of a TCR

2) There is no class switch recombination (CSR) or Somatic Hypermutation

Question 4

TCR transduce signals through ______

Answer 4

CD3

Question 5

Why is CD3 necessary in TCRs?

Answer 5

TCR recognizes antigen but does not have intracellular tails. So CD3 sends transduce signal.

Question 6

T cells respond to antigen from _____ a host cell

Answer 6

T cells respond to antigen from inside a host cell

Question 7

Pathogen and protein antigens get into host cells by: ____, or _____ or ______

Answer 7

Pathogen and protein antigens get into host cells by: Infection, or endocytosis or phagocytosis

Question 8

TCR must interact with ____ + ____ in order to be activated

Answer 8

TCR must interact with MHC + Peptide in order to be activates

Question 9

MHC class I is expressed on _____ cells and interact with CD_.

Answer 9

MHC class I is expressed on nucleated cells and interact with CD8.

Question 10

MHC class II is expressed on _____ cells (3 types): _____cells, ____cells, and ______. These interact with CD__.

Answer 10

MHC class II is expressed on antigen-presenting cells (3 types): dendrite cells, B cells, and macrophages.

Question 11

CD8 and CD4 are co-receptors that 1)______ and 2) _____.

Answer 11

CD8 and CD4 are co-receptors that 1) stabilize binding and 2) enhance signaling

Question 12

Activated CD4+ T cells produce ______, which are proteins that _______

Answer 12

Activated CD4+ T cells produce cytokines, which are proteins that signal other cells

Question 13

Activated CD8+ T cells become _______. Which _____ other cells

Answer 13

Activated CD8+ T cells become cytotoxic T lymphocytes (CTL). Which kill other cells

Question 14

The 2 co-receptors are _____ and ____

Answer 14

CD4 and CD8

Question 15

The ______ is the primary lymphoid organ for T cell development

Answer 15

The thymus is the primary lymphoid organ for T cell development

Question 16

Precursor of T-cell migrates from _____ to ______

Answer 16

Precursor of T-cell migrates from bone marrow to thymus

Question 17

If the thymus is absent ______ will be absent

Answer 17

If the thymus is absent mature T cells will be absent

Question 18

Syndrome due to little or no thymus and results in lack of mature T cells and recurrent infections. It affects heart and parathyroids and patients have characteristic facial features.

Answer 18

DiGeorge Syndrome.

Question 19

______ enters the thymus from the bone marrow.

Answer 19

Lymphoid progenitor

Question 20

______ (____recombination) rearrange and form a _____

Answer 20

TCR genes (V(D)J recombination) rearrange and form a Double negative thymocyte

Question 21

Double negative Thymocyte

Answer 21

No CD4 or CD8

Question 22

After TCR gene rearrangement a _____ thymocyte is formed

Answer 22

After TCR gene rearrangement a double positive thymocyte is formed

Question 23

Double positive thymocyte

Answer 23

Has CD4+ and CD8+

Question 24

Double positive thymocyte

Answer 24

Has CD4+ and CD8+

Question 25

In the cortex of the thymus, the double positive thymocyte undergoes _____

Answer 25

positive selection

Question 26

Positive selection

Answer 26

Select for T-cels that bind to patient’s own MHCs

Question 27

After positive selection, _____ takes place in the _____

Answer 27

After positive selection, negative takes place in the thymus medulla

Question 28

Negative selection

Answer 28

Deletion of self-reactive CD4+ and CD8+ cells