2.5

Question 1

Induction and effector phases of cell-mediated immunity (2)

Answer 1

leukocyte activation (inflammation); phagocytosis and killing of microbes 
CTL killing of infected cell

Question 2

effector functions

CD4+:

Answer 2

activation of macrophages, b cells, other cells

Question 3

effector functions

CD8+:

Answer 3

killing of infected “target cells”; macrophage activation

Question 4

Adhesion molecules on T cells stabilize binding to —

Answer 4

APCs

Question 5

LFA-1 is an

Answer 5

integrin protein

Question 6

ICAM-1 is a

Answer 6

ligand

Question 7

resting (costimulator-deficient) APC

T cell response:

Answer 7

no response or tolerance

Question 8

activated APC: increased expression of costimulators, secretion of cytokines
t cell response:

Answer 8

t cell proliferation and differentiation

Question 9

Inhibitory receptors are necessary for

Answer 9

limiting/terminating immune responses

Question 10

name: CD28

major function:

Answer 10

activation

naive t cells

Question 11

name: CTLA-4

major function:

Answer 11

inhibition

mediates suppressive function of regulatory T cells

Question 12

name: ICOS

major function:

Answer 12

activation

follicular helper T cells in antibody responses

Question 13

name: PD1

major function:

Answer 13

inhibition

Question 14

APCs	that	engulf	virus	infected	cells	(source	of	class	II	MHC	peptides)	and	also	are	infected	themselves	
(source	of	class	I	MHC	peptides)	will	have

Answer 14

antigens presented by both class I and II MHC molecules.

Question 15

These APCs engage both

Answer 15

CD4+ T cells (via Class II MHC) and CD8+ T cells (via Class I MHC).

Question 16

In this case the — T cell helps activate the — T cell.

Answer 16

CD4+

CD8+

Question 17

Principal function of IL-2:

Answer 17

survival and proliferation of antigen-specific T cells

Question 18

Subsets ofCD4+ T cells

distinguished by their

Answer 18

cytokine profiles: (Th1,

Th2, Th17)

Question 19

Development of effector CD4+ T cells

Answer 19

tfh cells remain in lymphoid organ, migrate into follicles
help b cells to produce high affinity antibodies
effector t cells and ab enter circulation and go to sites of infection
elimination of microbes

Question 20

cd4+ t cells activate macrophages, b lymphocytes
effector functions of activated macrophages, b lymphocytes

cell mediated immunity:

Answer 20

macrophage activation and killing of phagocytosed microbes

Question 21

cd4+ t cells activate macrophages, b lymphocytes
effector functions of activated macrophages, b lymphocytes

humoral immunity

Answer 21

secretion of ab with enhanced abilities to neutralize and eliminate antigens