T-Cell Mediated Diseases

Question 1

5 circumstances that can lead to a T cell mediated disease

Answer 1

autoantigens, transplant antigens, persistent antigens, superantigens, inappropriate antigens

Question 2

initiation of type IV hypersensitivity reaction

Answer 2

APC present antigen to CD4+ T cell –> will create sensitized Th1 and CD8+ cells

Question 3

antigen-presenting cells

Answer 3

macrophages, Langerhans cells

Question 4

effector phase of type IV hypersensitivity

Answer 4

sensitized Th1 cell –> secretes IFN-gamma –> activated macrophage

Question 5

effects of macrophage activation

Answer 5

increase MHC-II molecules, TNF receptors, oxygen radicals, and nitric oxide

Question 6

effectors in type IV hypersensitivity

Answer 6

chemokines, IFN-gamma, TNF-alpha/LT, IL-3/GM-CSG

Question 7

chemokines

Answer 7

attract macrophage to site of antigen

Question 8

IFN-gamma

Answer 8

expression of vascular adhesion molecules, activation of macrophages

Question 9

TNF-alpha/LT

Answer 9

local tissue destruction, adhesion molecules

Question 10

IL-3/GM-CSF

Answer 10

monocyte production by bone marrow

Question 11

3 examples of type IV hypersensitivity reactions

Answer 11

type I diabetes, MS, RA, Chron’s, tb skin test, graft rejection, lung tissue damage in tb

Question 12

binding properties of superantigens

Answer 12

bind the outside of MHC-II and the beta region (V chain) of TCR

Question 13

example of superantigen diseases

Answer 13

TSS, foot poisoning, rheumatic fever