Immune recognition and immune tolerance

Question 1

A thymocyte
a. initially produced either CD4 or CD8 before undergoing selection b. is a cell of the thymus medulla or epithelium
c. undergoes negative selection, followed by positive selection
d. undergoes positive selection in the thymis medulla
e. undergoes positive selection for MHC affinity

Answer 1

e

Question 2

T-cells do not destroy body cells because
a. Self-cells don’t present antigen
b. T-cell receptors cannot be produced that recognise self antigen
c. Self-cells possess a protective mechanism that protects them from T- cell-mediated cytotoxicity
d. self-reactive T-cells are inactivated before maturation e. B-cells produce antibody against self-reactive T cells

Answer 2

d

Question 3

Self-reactivity for T cells is selected out by
a. negative selection, in thymic medullary epithelial cells
b. positive selection, in thymic medullary epithelial cells c. negative selection, in the thymic cortex
d. positive selection, in the thymic cortex
e. anergy, in the thymic cortex

Answer 3

a

Question 4

Anergy is
a. permanent inactivation of a T cell
b. apoptotic cell death of a T cell
c. overstimulation of a T cell causing a cytokine storm
d. decline in function of an old T cell
e. a temporarily inactive T cell that has been ‘turned off’ by a Treg

Answer 4

a

Question 5

nTregs
a. develop in the periphery
b. have a constant low-level exposure to antigen
c. are produced in the thymus
d. regulate responses to food antigen
e. are induced by antigen

Answer 5

c

Question 6

Treg deficiency causes
a. autoimmunity
b. immune deficiency
c. lack of immune memory
d. absence of antibody production
e. leukaemia

Answer 6

a

Question 7

Detection of pathogen-associated molecular patterns leads to
a. migration of B cells to the bone marrow
b. migration of T cells to the thymus
c. migration of antigen-presenting cells to secondary lymphoid organs
d. upregulation of T-cell receptors
e. upregulation of antibody secretion

Answer 7

c

Question 8

Activated antigen-presenting cells interact with T cells
a. in the blood
b. in the spleen
c. in the thymus
d. in lymph nodes
e. in the bone marrow

Answer 8

d

Question 9

B-memory cells reside mainly
a. in the bone marrow
b. in the blood
c. in the thymus
d. in the lymph nodes
e. in the spleen

Answer 9

e