Helper T cells- Response to antigen

Question 1

Lymphocytes populations: Four major populations w/ antigen binding receptors

Answer 1

Helper T cells= regulate immune response
Cytotoxic T cells= destroy cells expressing endogenous antigens
Regulatory T cells= control everything
B cells= produce antibodies (adaptive immune response)

Question 2

Main role of Th cells?

Answer 2

important cell regulator of the immune response

Question 3

What would happen if helper T cells were not activated?

Answer 3

no immune response, no activation of B cells or cytotoxic T cells

Question 4

TCR

Answer 4

made of 2 proteins
variable region where antigen attaches 
α/β protein
γ/δ protein
-T cells
-30,000 TCR receptors

Question 5

MHC I

Answer 5

Big protein, α protein, microglobin

Question 6

MHC II

Answer 6

α/β protein

Question 7

BCR

Answer 7

similar to antibody, same chemical structure!
Big
-attached to cell membrane
-5 different types of receptors

Question 8

T cell antigen receptor

• humans & mice
• cows/sheep/pigs

Answer 8

• α/β protein

- γ/δ protein

Question 9

CD3 complex

Answer 9

• 5 protein chains (γ/δ/ε/η/ζ)
• protein dimers
• Complementary determining region (CDR)- recognize specific antigens
• Hypervariable sequence of amino acids

Question 10

Antigen-presenting cell (normal)

*What kind of response?

Answer 10

• Dendritic cell
• MHC II antigen
• CD4
• interacting w/ T cell (Th)
• humoral immune response

Question 11

Antigen-presenting cell (infected w. bact.)

*What kind of response?

Answer 11

• Cytotoxic T cell
• MHC I antigen
• CD8
• cellular immune response

Question 12

TCRα

Answer 12

to recognize antigen & MHC

Question 13

TCRγ

Answer 13

to recognize antigen

Question 14

CD3

Answer 14

signal transducer

Question 15

CD4

Answer 15

MHC II receptor

Question 16

CD8

Answer 16

MHC I receptor

Question 17

1st co-stimulatory signals

Answer 17

-APC: IL-1,6,8,12, TNFα, CCL3 (antigen presenting cells produce all these cytokines) proinflammatory cytokines

Question 18

2nd co-stimulatory signals

Answer 18

-APC CD28-CD80
-B cells CD28-CD86
B cells can act as APC
ACTIVATION-8 fold

Question 19

3rd co-stimulatory signals

Answer 19

CD152-CD80/86

INACTIVATION- T cell suppression

Question 20

T cells IL-2

Answer 20

upregulate cell survival genes, increase energy metabolism, promotes T cell division

Question 21

2 different types of dendritic cells:

Answer 21

• Myeloid precursor: Th1=cellular

- Lymphoid precursor: Th2=antibody/humoral

Question 22

Th17 cell

Answer 22

promote adaptive immune response

Question 23

IL-17

Answer 23

increase inflammation

Question 24

Helper T cell

Answer 24

antibody/humoral mediated cell response

Question 25

The variable domatin of the TCR is explicit for binding a specific antigen. T/F

Answer 25

TRUE

Question 26

TCR, BCR, MHC I & MHC II are not members of the immunoglobulin superfamily. T/F

Answer 26

FALSE: they ARE members

Question 27

If a processed and presented antigen bind in a correct manner on a T cell, T cell is activated and initiates the immune response by:

Answer 27

cytokine production, mitosis, cell differentiation

Question 28

CD3 is found in all T cells and it has a main role in the signal transduction into the T cell. T/F

Answer 28

TRUE