autoimmunity

Question 1

immunological tolerance

Answer 1

unresponsiveness to antigens induced by previous exposure

Question 2

tolerogens

Answer 2

antigens that induce tolerance

Question 3

self-tolerance

Answer 3

tolerance to self-antigens

Question 4

failure of self tolerance leads to

Answer 4

autoimmune diseases

Question 5

autoimmune disease can be avoided by

Answer 5

central and peripheral tolerance

Question 6

central and peripheral tolerance

Answer 6

eliminate or down-regulate self-reactive molecules in T and B cells

Question 7

important organs for central tolerance

Answer 7

thymus: eliminates T cells with high affinity to self-antigens

bone marrow: B cell tolerance

Question 8

central tolerance

Answer 8

thymus eliminates T cells with high affinity to self antigens

bone marrow eliminates B cells with high affinity to self antigens

Question 9

peripheral tolerance

Answer 9

anergy (functional unresponsiveness)

antigen recognition without co-stimulation

T_reg suppression

deletion (cell death)

self-antigens hidden from immune system by anatomical barriers

Question 10

autoimmunity

Answer 10

adaptive immune response to self antigens

Question 11

autoantibodies

Answer 11

antibodies directed at normal cellular components

most healthy individuals produce some autoantibodies (low level and affinity)

Question 12

autoimmune disease

Answer 12

autoreactive T cells or autoantibodies cause tissue damage through hypersensitivity reaction types II, III, IV

Question 13

antibodies

Answer 13

B cells secrete antibodies that are major source of autoantibodies

• activate complement
• cross-react with inherited A and B antigens of red cells
• bind to normal cellular constituents (eg nuclear proteins and DNA)

Question 14

breakdown of T cell tolerance occurs due to?

Answer 14

genetic factors: polymorphisms, diseases, MHC alleles

environmental factors: infections, drugs, UV radiation

Question 15

molecular mimicry

Answer 15

structural similarity between self proteins and microbial antigens may trigger an immune response

Question 16

genetic predispositions to breakdown of T cell tolerance

Answer 16

gene mutations: AIRE

polymorphisms: MHC, MBL, insulin gene, complement C1

Question 17

epidemiology of autoimmune disease

(prevalence, age, sex)

Answer 17

• prevalence 3%
• peak onset: 15-65 years (exception T1 diabetes)
• woman (exception ankylosing spondylitis)

Question 18

non-organ specific autoimmune diseases

Answer 18

affect multiple organs

associated with autoimmune responses against self-molecules

intracellular molecules involved in transcription and translation

Question 19

organ specific autoimmune disease

Answer 19

restricted to one organ

endocrine glands

Question 20

SLE

Answer 20

Question 21

autoimmune disease treatment

Answer 21

suppression of damaging immune response

replacement of the function of the damaged organ