L39 immunolgical Tolerance powell

Question 1

Immunolgical tolerance

Answer 1

Learned, specific unresponsiveness induced by prior exposure

Question 2

Choice between lymphocyte activation and tolerance determined by

Answer 2

Properties/quantity of antigen
State of maturation
Stimuli received when encounter happens

Question 3

Fate of B cells depends on

Answer 3

nature and concentration of self Ag

Question 4

Suppression occurs thru

Answer 4

CD4/CD25 Reg T cells secreting TGF-Beta or IL-10

Question 5

Factors determining which mechanisms are operative

Answer 5

Concentration of self antigen
Affinity of antigen receptor for antigen
Nature of antigen
Concentration and availability of co-stimulatory molecuels

Question 6

How do T cells affect outcome of B cell activation

Answer 6

Signal one: gnerated thru Ag receptor
Signal two: mediated by CD40 and CD40L
B-Cell anergy if one is missing

Question 7

Systemic examples

Answer 7

Lupus (SLE)

rheumatoid arthritis

Question 8

Organ specific examples

Answer 8

Insulin dependent Diabetes mellitus (Type I)

Multiple sclerosis