Autoimmunity Vs Autoimmune Disease

Question 1

Define autoimmunity

Answer 1

Immune response against host due to loss of immunological tolerance of self antigens

Question 2

Define autoimmune disease

Answer 2

Conditions caused by tissue damage or disturbed physiological responses due to immune response against self antigens

Question 3

Difference between organ specific + non organ specific autoimmune disease

Answer 3

• organ specific: one or multiple self antigens within one single organ or tissue
• non organ specific: widely distributed self antigens throughout the body (all cells)

Question 4

Describe immunological tolerance

Answer 4

A diverse range of host processes that prevent potentially harmful immune responses against host antigens

Question 5

Describe the mechanisms of induction of autoimmunity - breakdown of tolerance

Answer 5

• breakdown of central tolerance: failure to delete auto reactive T or B cells
• breakdown of peripheral tolerance: Treg defects | impaired immunomodulation | altered self antigens
• activation of auto reactive B cells: T cell independent activation of B cells |carrier effect (complex foreign self antigens)

Question 6

Examples of organ specific autoimmune diseases
What type of hypersensitivity reaction occurs in each?

Answer 6

• Hashimoto’s thyroiditis - type IV
• type 1 DM - type IV
• MS - type IV
• Good pasture’s syndrome - type II
• Addison’s disease - type II
• Graves disease - type II
• Myasthenia gravis - type II
• Pernicious anaemia - type II

Question 7

Examples of non organ specific autoimmune diseases
What type of hypersensitivity reaction occurs in each?

Answer 7

• autoimmune haemolytic anaemia - type II
• RA: type III
• systemic lupus erythematosus - type III
• Sjögren’s syndrome - type IV

Question 8

Diagnosis of autoimmune disease

Answer 8

• presence of autoantibodies/autoreactive T cells
• levels of autoantibodies correlate with disease severity
• autoantibodies/autoreactive T cells found at the site of tissue damage
• transfer of autoantibody or autoreactive T cells to healthy host induces an autoimmune disease
• family history
• clinical benefit provided by immunomodulatory therapy

Question 9

Define specificity

Answer 9

The ability of the test to excluded those who do not have the condition

Question 10

Define sensitivity

Answer 10

The ability of the test to identity those with a condition
think that you’re sensitive to something about you > you have the condition

Question 11

What disease is produced if there are maternal autoantibodies to;
- platelets
- RBCs
- TSH receptor
- acetylcholine receptor
- nuclear antigen SSA/Ro

Answer 11

• platelets: thrombocytopenia
• RBCs: haemolytic anaemia
• TSH receptor: neonatal Grave’s disease
• acetylcholine receptor: neonatal myasthenia gravis
• nuclear antigen SSA/Ro: neonatal systemic lupus erythematous

Question 12

Primary vs secondary autoantibodies

Answer 12

• primary: drive the disease
• secondary: occurs later in disease course + do no drive disease

Question 13

What genetic factors trigger autoimmunity?

Answer 13

• increased risk with affected sibling/identical twin
• AIRE mutations that affect central tolerance
• autoimmune disease associated with MHC variant

Question 14

What environmental factors trigger autoimmunity?

Answer 14

Hormones
Infections
Drugs

Question 15

Are autoimmune diseases more common in men or women?

Answer 15

Women

Question 16

Infectious causes of Gillian barre syndrome
What antigen is involved

Answer 16

• campylobacter jejune glycoproteins
• myelin-associated gangliosides

Question 17

Therapeutic strategies for autoimmune diseases

Answer 17

• plasma exchange: removes autoantibodies
• immunosuppressive drugs: suppresses autoreactive T cells
• anti inflammatory drugs to treat tissue damage
• replacement therapy surgery: to treat organ dysfunction

Question 18

what are the three main categories of breakdown of tolerance inducing autoimmunity?

Answer 18

• breakdown of central tolerance
• breakdown of peripheral tolerance
• activation of autoreactive B cells

Question 19

Future therapeutic alternative for autoimmune diseases

Answer 19

Monoclonal antibodies

Question 20

Two most common autoimmune diseases in UK

Answer 20

Systemic lupus erythematosus
Sjögren’s syndrome

Question 21

Why are there adverse drug reactions of immunosuppressive drugs?

Answer 21

No specific target therapies

Question 22

Examples of 4 primary autoantibodies + their related disease

Answer 22

• anti TSHR: Grave’s disease
• anti acetylcholine receptor: myasthenia gravis
• anti voltage gated Ca2+ channel: lambert Eaton myasthenia syndrome
• anti glomerular basement membrane: good pasture’s syndrome

Question 23

Examples of 4 secondary autoantibodies + their related disease

Answer 23

• anti nuclear: SLE
• anti gastric parietal cell: pernicious anaemia
• anti thyroid peroxydase: hashimoto thyroiditis
• anti rheumatoid factor: RA

Question 24

Two types of autoimmune disease

Answer 24

Organ specific
Non organ specific

Question 25

What autoimmune disease is detected via indirect immunofluorescence?

Answer 25

Type 1 diabetes mellitus Addison’s disease Pernicious anaemia Goodpasture’s disease (not indirect)

Question 26

What autoimmune disease are detected via radioimmunoassay?

Answer 26

Myasthenia gravis Systemic lupus erythematosus y

Question 27

What autoimmune diseases are treated by replacement therapy?

Answer 27

- Hashimoto’s thyroiditis - type 1 diabetes mellitus - pernicious anaemia - Addison’s disease

Question 28

What autoimmune diseases are treated using plasmapheresis?

Answer 28

Goodpasture’s syndrome Myasthenia gravis

Question 29

Answer the following for Hashimoto’s disease: - self antigen - hypersensitivity reaction - clinical outcome - technique to identify - therapy/treatment

Answer 29

- **self antigen**: anti TPO + thyroglobulin - **hypersensitivity reaction**: type 4 - **clinical outcome**: hypothyroidism - **technique to identify**: infiltration of T cells - **therapy/treatment**: replacement therapy

Question 30

Answer the following for type 1 DM: - self antigen - hypersensitivity reaction - clinical outcome - technique to identify - therapy/treatment

Answer 30

- **self antigen**: pancreatic islet cells - B cells - **hypersensitivity reaction**: type 4 - **clinical outcome**: hyperglycaemia - **technique to identify**: indirect immunofluroscence - **therapy/treatment**: insulin

Question 31

Answer the following for MS: - self antigen - hypersensitivity reaction - clinical outcome - therapy/treatment

Answer 31

- **self antigen**: oligodendrocytes in myelin sheath - **hypersensitivity reaction**: type 4 - **clinical outcome**: demyelinating disease - **therapy/treatment**: anti inflammatories

Question 32

Answer the following for Goodpasture’s disease: - self antigen - hypersensitivity reaction - clinical outcome - technique to identify - therapy/treatment

Answer 32

- **self antigen**: glomerular basement membrane - **hypersensitivity reaction**: type 2 - **clinical outcome**: glomerulonephritis - **technique to identify**: immunofluorescence - **therapy/treatment**: plasmapheresis + dialysis

Question 33

Answer the following for Addison’s disease: - self antigen - hypersensitivity reaction - clinical outcome - technique to identify - therapy/treatment

Answer 33

- **self antigen**: steroid-21 hydroxylase - **hypersensitivity reaction**: type 2-4 - **clinical outcome**: adrenal insufficiency - **technique to identify**: indirect immunofluroescence - **therapy/treatment**: replacement therapy

Question 34

Answer the following for Grave’s disease: - self antigen - hypersensitivity reaction - clinical outcome - therapy/treatment

Answer 34

- **self antigen**: TSH - **hypersensitivity reaction**: 2 - **clinical outcome**: hyperthyroidism - **therapy/treatment**: antithryoid drugs, surgery + plasmapheresis

Question 35

Answer the following for Myasthenia gravis: - self antigen - hypersensitivity reaction - clinical outcome - technique to identify - therapy/treatment

Answer 35

- **self antigen**: ACh receptors on neuromuscular junction - **hypersensitivity reaction**: type 2 - **clinical outcome**: skeletal muscle weakness - **technique to identify**: radioimmunotherapy - **therapy/treatment**: anticholinesterase + immunosuppressive drugs

Question 36

Answer the following for pernicious anaemia: - self antigen - hypersensitivity reaction - clinical outcome - technique to identify - therapy/treatment

Answer 36

- **self antigen**: intrinsic factor - **hypersensitivity reaction**: type 2 - **clinical outcome**: vitamin B12 deficiency - **technique to identify**: indirect immunofluorescence - **therapy/treatment**: B12 injection - hydroxocobalamin

Question 37

Answer the following for SLE: - self antigen - hypersensitivity reaction - clinical outcome - technique to identify - therapy/treatment

Answer 37

- **self antigen**: dsDNA + histones - **hypersensitivity reaction**: type 3 - **clinical outcome**: multisystem disease - **technique to identify**: radioimmunity - **therapy/treatment**: immunosuppressives

Question 38

Answer the following for autoimmune haemolytic anaemia: - self antigen - hypersensitivity reaction - clinical outcome - technique to identify - therapy/treatment

Answer 38

- **self antigen**: RBC antigens - **hypersensitivity reaction**: type 2 - **clinical outcome**: anaemia - **technique to identify**: Coombs test - **therapy/treatment**: anti-inflammatory drugs/splenectomy

Question 39

Answer the following for RA: - self antigen - hypersensitivity reaction - clinical outcome - technique to identify - therapy/treatment

Answer 39

- **self antigen**: Rheumatoid factor (Fc potion of IgG) - **hypersensitivity reaction**: type 3-4 - **clinical outcome**: inflammatory arthritis + systemic features - **technique to identify**: aggulation - **therapy/treatment**: immunosuppressives

Question 40

Answer the following for Sjogren’s syndrome: - self antigen - hypersensitivity reaction - clinical outcome - technique to identify - therapy/treatment

Answer 40

- **self antigen**: nuclear antigens - **hypersensitivity reaction**: type 4 - **clinical outcome**: dry eyes + mouth + arthritis - **technique to identify**: immunofluorescence - **therapy/treatment**: immunosuppressive drugs + monoclonal antibodies

Question 41

What are the autoantibodies in RA?

Answer 41

Anti-cyclic citrullinated peptide Rheumatoid factor

Question 42

What drug is used to treat Grave’s disease? What is it’s mechanism of action?

Answer 42

**carbimazole** - Thyroid peroxidase inhibitor - less iodination of tyrosine - less oxidative coupling of iodinated tyrosine