Test 2: T cell Function

Question 1

What is the difference between the 2 types of T cells?

Answer 1

CD4 helper T cells: produce cytokine that activate and recruit other cells

CD8 cytotoxic T cells: kill infected cells

Question 2

What can T cell receptors recognize?

Answer 2

T cell receptor recognition is VERY specific
- T cell clones express TCR that can only recognize one peptide/MHC complex

Question 3

What does Th1 make?

Answer 3

IFNy which activates macrophages

Question 4

What does Th2 make?

Answer 4

IL4, IL5, IL3 which activate eisonphils

Question 5

What does Th17 make?

Answer 5

IL22 which activate neutrophils

Question 6

What is involved in activation of macrophages by Th1 cells?

Answer 6

IFNy and CD40-CD40L

Question 7

What are the specific functions of Th2 cells?

Answer 7

• IL4 induces B cells to produce IgE
• IL5 induces eosinophil activation which mediates worm elimination

Question 8

What are the different macrophages functions?

Answer 8

M1 (classical): killing and inflammation
M2 (alternative): tissue repair and inhibit inflammation

Question 9

What are the functions of Th17 cells?

Answer 9

• remember, they produce IL17 and IL 22 which. give antimicrobial peptide production by epithelial cells
• IL17 mediates recruitment of neutrophils via induction of cytokines/chemokines production from other cells

Question 10

What is the function of T follicular helper cells?

Answer 10

• T follicular helper cells make IL21
• IL21 mediates production of Ig by B cells

Question 11

How does CD8 kill?

Answer 11

perforin and granzyme released from granules

Question 12

What is the difference between T cell vs APC recognizing antigen?

Answer 12

• T cells are very specific in that they only recognize peptide/MHC complex
• several peptides can be presented by different MHC molecules on the surface of the same dendritic cell (antigen presenting cell)

Question 13

What determines the fate of naive T cells?

Answer 13

the cytokines that are produced by dendritic cells or other innate cells recognizing different types of microbes

Question 14

What cytokines are involved in monocytes becoming M2 macrophages (alternate route)?

Answer 14

IL4 and IL13

Question 15

Other than perforin and granzyme, what is another way CD8 cells kill?

Answer 15

• Th1 cells activate macrophage to lyse intravesicular microbes
• CD8 kill infected cells with the help from Th1 cells