Autoimmunty

Question 1

What cell type can override Treg cells? [1]

Answer 1

Th17 by releasing IL-17

Question 2

What’s the difference between an autoimmune reaction and an autoimmune disease?

Answer 2

A disease is pathological and cause harm to tissues/organs

A reaction can be part of the normal bodily processes, attacking cells that are damaged, in the wrong place or neoplastic

Question 3

Autoimmune diseases can be split into 2 categories?

Answer 3

Organ specific with a single tissue specific Ab e.g. Anti-GAD

Non-Organ Specific with non-specific Abs e.g. ANA

Question 4

Give some examples of organ specific autoimmune diseases? [5]

Answer 4

Graves
Hashimotos
Myasthenia Gravis
Pernicious Anaemia
Type 1 DM

Question 5

Give some examples of non-organ specific autoimmune disorders? [4]

Answer 5

SLE
RA
Systemic Sclerosis
Systemic Vasculitis

Question 6

Try to list 5 different mechanisms of autoimmune disease?

Answer 6

1) Cell Mediated Autoimmunity
2) Antibody Mediated (Type 2 hypersensitivity)
3) Immune complex mediated (Type 3 hypersensitivity)
4) Innate Recruitment
5) Molecular Mimicry

Question 7

What conditions operate by cell mediated autoimmunity? [3]

What immune cells are involved? [2]

Answer 7

Type 1 DM
Psoriasis
Coeliac disease

T & NK cells are involved

Question 8

What major conditions operate by antibody mediated autoimmunity? [2]

Answer 8

Goodpasture’s Syndrome

Myasthenia Gravis

Question 9

What happens in good pastures syndrome? [2]

Answer 9

Anti-GBM Abs react to type 4 collagen in the basement membrane –> lung haemorrhage & glomerulonephritis

Question 10

What happens in Myasthenia gravis?

Explain rationale for thymectomy

Answer 10

Auto-reactive T cells & Anti-Ach receptor Abs attach to receptors at NMJ [1]
Causing muscle weakness & fatigability [1]
It’s primarily an Ab disorder but T cells are involved hence why we look for and resect thymomas [1]

Question 11

Give an example of an Immune Complex mediated autoimmune disorder?

Answer 11

SLE

Question 12

How does molecular mimicry work?

Answer 12

A foreign antigen can initiate an immune response [1] in which a T or B cell component cross-recognizes self [1]

Question 13

Example of a condition that works by molecular mimicry? [3]

Answer 13

Rheumatic Fever

Strep carries an antigen very similar to that found on muscle cells –> Myocardial damage and myositis

Question 14

How can we treat autoimmune disorders? [6]

Answer 14

• Anti-inflammatories
• Immunosuppresants e.g. MTX, CCS
• Plasmapheresis
• Stem cell/marrow transplant
• Replacing lost physiological factors
• Organ/tissue graft