Session 3

Question 1

Define autoimmunity

Answer 1

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

Question 2

Define autoimme disease

Answer 2

Disease caused by tissue damage or disturbed physiological responses due to an auto-immune response

Question 3

What are the two different forms of autoimmune disease?

Answer 3

Organ specific and non-organ specific

Question 4

What is an organ specific autoimmune disease?

Answer 4

One or multiple self antigens within one single organ or tissue

Question 5

What is a non-organ specific autoimmune response?

Answer 5

Wide distributed self antigens throughout the body

Question 6

Give some examples of organ specific autoimmune diseases?

Answer 6

Hashimoto’s thyroiditis, graves disease, type I diabetes, multiple sclerosis

Question 7

Give some examples of non-organ specific autoimmune diseases?

Answer 7

Autoimmune haemolytic anaemia, rheumatoid arthiritis, systemic lupus erthematosus

Question 8

What are the immune mechanisms of tissue damages involved in autoimmune diseases?

Answer 8

Autoantibodies and auto reactive T cells

Question 9

How do autoantibodies cause tissue damage?

Answer 9

• Complement activation
• Antibody-mediated cell cytotoxicity
• Neutrophil activation

Question 10

How do autoreactive T cells cause tissue damage?

Answer 10

• Cytotoxic T cells

- Macrophages

Question 11

How would you go about diagnosing an autoimmune disease?

Answer 11

• Blood test (serology)
• Presence of autoantibodies/autoreactive T cells
• Levels of autoantibodies correlate with disease severity
• Autoantibodies/autoreactive T cells found at the site of tissue damage

Question 12

What is the different between a primary antibody and a secondary antibody?

Answer 12

Primary - antibody is present at the start of the disease

Secondary - antibody appears during the board of the disease

Question 13

What is the final 3 stages of diagnosing someone with an autoimmune disease?

Answer 13

• Transfer of autoantibody or auto reactive T cells to a healthy host induces the autoimmune disease.
• Clinical benefit provided by immunomodulatory therapy
• Family history

Question 14

What are the main different mechanisms of induction of autoimmunity? (how do they start)

Answer 14

• Breakdown of central tolerance
• Breakdown of peripheral tolerance
• Activation of auto reactive B cells

Question 15

How can the breakdown of central tolerance cause an autoimmune disease?

Answer 15

Failure to delete auto reactive T cells

Question 16

How does breakdown of peripheral tolerance cause an autoimmune disease?

Answer 16

• Regulatory T cells defects
• Impaired immunomodulation
• Altered self antigens

Question 17

How does activation of auto reactive B cells induce autoimmunity?

Answer 17

• T cell-independent activation of B cells

- Carrier effect (complex foreign self antigens)

Question 18

What triggers autoimmunity?

Answer 18

• Genetic factors

- Environmental factors

Question 19

Give some examples of hormones that might trigger autoimmunity?

Answer 19

Hormones, infections and drugs