15. Cell-Mediated Immunity and Cytokines

Question 1

Besides CD2 and CD3, name other CD markers that are present on T helper cells, cytotoxic T cells, and T regulatory cells.

Answer 1

T helper cells = CD4
Cytotoxic T cells = CD8
T regulatory cells = CD4 and CD25

Question 2

Which subset(s) of T helper cells play a major role in assisting cell-mediated immune responses, which are beneficial in defense against viral and protozoal infections?

Answer 2

T Helper 1 (Type I response)

Question 3

Which subset(s) of T helper cells play a major role in assisting humoral immune responses, which are beneficial in defense against bacterial and helminth infections?

Answer 3

T Helper 2 (Type 2 response)

Question 4

What class of MHC antigen is recognized by cytotoxic T cells?

Answer 4

MHC class I

Question 5

How do cytotoxic T cells kill target cells in the body?

Answer 5

1. Direct contact with target cell
2. Release of perforin, creating pores in target cell
3. Release of granzyme B, resulting in target cell destruction

Question 6

production and functions of Interleukin 1 (IL-1)

Answer 6

Production: Macrophages
Function: Converts T helper from resting state to activated state; role in inflmmation, hematopoiesis, and fever

Question 7

production and functions of Interleukin 2 (IL-2)

Answer 7

Production: Activated T helper
Function: Induces proliferation of activated T helper and B cells; Induces maturation of CTL’s; causes activation of LAK cells (tumor immunity)

Question 8

production and functions of Interleukins 4 & 5 (IL-4; IL-5)

Answer 8

Production: Activated T helper
Function: Induce proliferation of B lymphocytes

Question 9

production and functions of Interleukin 6

Answer 9

Production: Activated T helper
Function: Induce differentiation of B lymphocytes

Question 10

production and functions of Tumor Necrosis Factor

Answer 10

Production: TNF alpha = Macrophages; TNF Beta = CTL and TH
Function: Cytotoxic effects on tumor cells, Activate endothelial cells and neutrophils in
acute inflammation.

Question 11

production and functions of Interferon alpha (IFN Type 1)

Answer 11

Production: Leukocytes (B, T, NK, Macrophages)
Function: Inhibit replication of viruses (all IFN’s)

Question 12

production and functions of Interferon beta (IFN Type 3)

Answer 12

Production: Fibroblasts
Function: Inhibit replication of viruses (all IFN’s)

Question 13

production and functions of Interferon gamma (IFN Type 2)

Answer 13

Production: Activated T cells (T helper, T cytotoxic)
Function: Inhibit replication of viruses (all IFN’s); Stimulation of Macrophages and Enhancement of NK activity (gamma only)

Question 14

production and functions of Interleukin 10 (IL-10) and Transforming Growth Factor Beta (TGF-B)

Answer 14

Production: Activated MF and T cells
Function: Inhibitory cytokines = Inhibit Ag presentation and other functions of
activated Macrophage

Question 15

production and functions of Interleukin 3 (IL-3) and Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF)

Answer 15

Production: T cells
Function: Human Growth Factor = induce differentiation of hematopoietic cells

Question 16

CCL5; CXCL3

Answer 16

Chemokines = a group of proteins that stimulate leukocyte
movement and regulate migration of
leukocytes from the blood to the tissues

Question 17

Which cytokines cause B cell proliferation and differentiation?

Answer 17

IL- 4, 5, 6

Question 18

Which cytokine causes T cell activation? T cell proliferation?

Answer 18

T cell activation = IL- 1

T helper cell proliferation = IL-2

Question 19

Which cytokines have anti-viral activity?

Answer 19

all INF’s inhibit replication of viruses

Question 20

Which cytokines have anti-tumor activity?

Answer 20

Tumor Necrosis Factors (TNF Alpha and Beta)

Question 21

Which cytokines inhibit the immune response?

Answer 21

Inhibitory cytokines = IL-10 and Transforming Growth Factor Beta

Question 22

Which cytokines promote hematopoiesis?

Answer 22

Human Growth Factors = IL-3, GM-CSF (Granulocyte-Macrophage

Colony Stimulating Factor)

Question 23

Which cytokines promote chemotaxis?

Answer 23

Chemokines = ex: CCL5, CXCL3