Autoimmunity Flashcards
Define autoimmunity. (2)
An immune response against the host due to the loss of immunological tolerance to self-antigens.
Define autoimmune disease. (2)
A disease caused by the tissue damage or disturbed physiological responses due to an autoimmune response.
Describe the two types of autoimmune reaction. (4)
Organ specific - autoantibodies against a one-organ antigen. Can still have systemic effects.
Non-organ specific - widely distributed antigens
Describe the consequences of an autoimmune reaction. (3)
A hypersensitivity reaction is prompted, leading to tissue fibrosis that impairs function and will be unresponsive to treatment.
Name three autoimmune diseases that can be passed onto foetuses and present in the newborn. Explain why these can. (5)
Graves’ disease, SLE and DMII. These have autoantibodies that are IgG, so can be passed on to the baby through the placental circulation.
Name the self antigen, the result, the organ specificity and the type of hypersensitivity for: Hashimoto’s thyroiditis. (5)
Antigen: thyroid peroxidase and thyroglobulin
Result: hypothyroidism
Organ specific
Type of hypersensitivity: IV
Name the self antigen, the result, the organ specificity and the type of hypersensitivity for: DMI (4)
Antigen: pancreatic islet cells
Result: hyperglycaemia
Organ specific
Type of hypersensitivity: IV
Name the self antigen, the result, the organ specificity and the type of hypersensitivity for: Multiple Sclerosis (4)
Antigen: myelin sheath
Result: demyelination
Organ specific
Type of hypersensitivity: IV
Name the self antigen, the result, the organ specificity and the type of hypersensitivity for: Goodpasture’s Disease (5)
Antigen: glomerular / alveolar basement membrane
Result: glomerulonephritis
Organ specific
Type of hypersensitivity: II
Name the self antigen, the result, the organ specificity and the type of hypersensitivity for: Addison’s Disease (5)
Antigen: steroid-21 hydroxylase in adrenal cortex
Result: adrenal insufficiency
Organ specific
Type of hypersensitivity: unknown (II / IV)
Name the self antigen, the result, the organ specificity and the type of hypersensitivity for: Graves’ Disease (4)
Antigen: thyroid stimulating hormone receptor
Result: hyperthyroidism
Organ specific
Type of hypersensitivity: II
Name the self antigen, the result, the organ specificityand the type of hypersensitivity for: Myasthenia Gravis (4)
Antigen: acetylcholine receptors in neuromuscular junction
Result: skeletal muscle weakness
Organ specific
Type of hypersensitivity: II
Name the self antigen, the result, the organ specificity and the type of hypersensitivity for: Pernicious anaemia (4)
Antigen: intrinsic factor in the terminal ileum
Result: B12 deficiency
Organ specific
Type of hypersensitivity: II
Name the self antigen, the result, the organ specificity and the type of hypersensitivity for: Autoimmune haemolytic anaemia (4)
Antigen: red blood cell antigens
Result: anaemia
Not organ specific
Type of hypersensitivity: II
Name the self antigen, the result, the organ specificity and the type of hypersensitivity for: Rheumatoid arthritis (4)
Antigen: rheumatoid factor on IgG
Result: inflammatory arthritis
Not organ specific
Type of hypersensitivity: IV
Name the self antigen, the result, the organ specificity and the type of hypersensitivity for: SLE (5)
Antigen: dsDNA and histone proteins
Result: multisystem disease
Not organ specific
Type of hypersensitivity: III
Name the self antigen, the result, the organ specificity and the type of hypersensitivity for: Sjogens’ Syndrome (5)
Antigen: nuclear antigens
Result: dry eyes and mouth, arthritis
Not organ specific
Type of hypersensitivity: IV
Describe the six criteria for diagnosing autoimmunity. (6)
1 - presence of autoantibodies or autoreactive T cells.
2 - levels of autoantibodies correlate to disease severity.
3 - autoantibodies / autoreactive T cells are found at the site of tissue damage.
4 - transfer of autoantibodies or autoreactive T cell into a healthy host will induce the disease in the host.
5 - clinical benefit provided by immunomodulatory therapy.
6 - Family history
Name four factors that increase the risk of developing autoimmune disease. (4)
Hormonal
Infectious
Drugs
Genetics.
Describe the effects of hormones on the chances of developing an autoimmune disease. (3)
All autoimmune diseases are more common in women (esp SLE, Hashimoto’s, Graves). Suggests a link with oestrogen or prolactin.
Describe the links between certain autoimmune diseases and infections. (6)
Strep pyogenes M protein and Rheumatoid arthritis
Campylobacter jejuni glycoproteins and Guillian-Barré
Coxsakieviruse nuclear protein and DMI.
Describe the links between certain autoimmune diseases and drugs. (10)
D penicilamine (used for RA) and SLE, glomerulonephritis, and myasthenia Gravis. Methyl-dopa (antihypertensive) and haemolytic anaemia Hydralazine (antihypertensive), procainamide (anti-arrythmic) and isoniazid (anti-TB) associated with SLE.
Describe the types of autoantibody. Give two examples of each. (8)
Primary - autoantibody is responsible directly for the tissue damage - Graves’, myasthenia Gravis.
Secondary - autoantibody is associated with the disease but finding it is not diagnostic alone - SLE, RA.
Describe the treatments of: Hashimoto’s thyroiditis
Replacement therapy - levothyroxine
