Immunology

Question 1

four environmental factors that can induce autoimmunity?

Answer 1

1. molecular mimicry
2. intercurrent infections
3. tissue damage
4. superantigens

Question 2

define molecular mimicry

Answer 2

foreign components break tolerance to self-antigens

Question 3

define intercurrent infections

Answer 3

immune responses can potentiate ongoing AI reactions

Question 4

define tissue damage/ antigen sequestration

Answer 4

self antigens that were hidden are released

Question 5

what is myasthenia gravis?

Answer 5

autoantibodies (IgG) that bind to ACh receptors

Question 6

what other autoimmune conditions is myasthenia gravis associated with?

Answer 6

SLE
RA
thyrotoxicosis

Question 7

pathophysiology of myasthenia gravis

Answer 7

1. Th cells stimulate B cells leading to production of anti-AChR IgG
2. thymic cells are attacked and immune complexes form
3. these block ACh binding leading to defective nerve transmission
4. muscle endplate is destroyed