T cells lecture 2

Question 1

What are 3 types of APCs that express both MCH-1 and MHC-II

Answer 1

Dendritic Cells
Activated macrophages
Activated B cells

Question 2

Other cells that are not APCs and express MHC-I are known as?

Answer 2

Target cells
Virus infected
Malignant
Aging cells
Cells from graft

Question 3

Why can’t we fight all viruses?

Answer 3

Virus are diverse
Evolve
Selection

Question 4

What is the role of T cells in the immune system?

Answer 4

Immune response
Activate CD4 and CD8 against virus, bacteria and parasites
Activated in response to tumour cells
Cells from foreign grafts

Question 5

How naive T cells activated against pathogens?

Answer 5

Dendritic cells take up pathogens and traffic to the lymph node
Lymph node- interact with T cells
Activate T helper cells and Killer T cells

Question 6

T helper cell humoural and cell-mediated responses

Answer 6

APC
- peptide antigen on MHC class II
interacts with TCR of CD4 T cell
Differentiates in helper T cell and produce cytokines
Help CD8 - attack
B cell - secrete antibodies

Question 7

T helper cell humoural and cell-mediated responses: cytokines produced

Answer 7

IL-2
IL-4
IFN

Question 8

IL-2
IL-4
IFN

Answer 8

Priming and helping the B cell

Question 9

Bacteria targeted by

Answer 9

CD4+ T cell

Question 10

Activation of CD4+ release

Answer 10

Cytokines

Question 11

Release of cytokines stimulate

Answer 11

Macrophages
CD8 T cell
D cells

Question 12

Viral infected cells are killed by

Answer 12

CD8+ T cells

Question 13

Two signal model of T cell

Answer 13

Co-stimulation

Question 14

2 signal needed for T cell activation

Answer 14

1. MHC and TCR
2. B7.1/B7.2 and CD28 (found on T cell) `

Question 15

B7.1/B7.2 is what type of molecule?

Answer 15

Co-stimulatory molecule
Always expressed APC

Question 16

Clonal expansion

Answer 16

Many T cell with T cell receptor specific
For specific MHC/peptide complex

Question 17

Co-stimulation and clonal expansion mechanism

Answer 17

1. TCR and specific MHC peptide complex binding
2. 2 signals- B7 (apc) CD28 (T cell)
3. T cell produce IL-2 (triggers proliferation)
4. several division -> population of memory and effector cell

Question 18

CD8+T cell killing

Answer 18

CD8+T interact with APCs
Detect pathogen peptides on MHC molecules
T cell become activated-> differentiate into cytotoxic T cells

Question 19

CD8+T weapons

Answer 19

Perforin
Granzymes
Grulysin

Question 20

Perforin

Answer 20

Aids delivering contents of granules into the cytoplasm

Question 21

Granzymes

Answer 21

Serine proteases
Initiate apoptosis once injected into cytoplasm

Question 22

Granulysin

Answer 22

Antimicrobial

Question 23

What do CD8+T cell release into the target cell?

Answer 23

Cytotoxic granules

Question 24

T cell development un thymus: initially

Answer 24

Double negative
Don;t have CD4 / CD8 receptor

Question 25

DN3

Answer 25

Double negative 3
Pre TCR
VDJ recombination (thymus)
Not mature

Question 26

DN4

Answer 26

Prolifieration

Question 27

Double-positive

Answer 27

CD4 and CD8 TCR

Question 28

Single positive

Answer 28

CD4 TCR or CD8 TCR

Question 29

Positive Selection

Answer 29

T cells
-TCR
-Recognise MHC and self peptide
-selected for survival

Question 30

Negative selection

Answer 30

T cells that recognise MHC and self peptide too well are deleted