Autoimmunity

Question 1

What is tolerance?

Answer 1

A state of unresponsiveness of the immune system to self

Question 2

What is autoimmunity?

Answer 2

The failure of an organism in recognising its own constituent parts as being ‘self’

Question 3

What causes autoimmunity?

Answer 3

Immune regulation
Unknown
Hormonal
Environment
Genetic Factors

Question 4

What is an autoimmune disease?

Answer 4

Immune response contributing directly to

tissue / organ damage.

Question 5

Who is more prone to autoimmune disease?

Answer 5

Females > males

Question 6

What are the three categories of autoimmune disease?

Answer 6

Cell mediated
Antibody Mediated
Mixed/Atypical reactions

Question 7

Give examples of cell mediated autoimmune diseases?

Answer 7

DM type 1, Crohn’s, psoriasis

Question 8

What is an antibody mediated autoimmune reaction?

Answer 8

Where antibody binds to targets leading to damage by Fc receptor macrophage with or without complement lysis

TYPE 2 REACTION

Question 9

Give examples of antibody mediated autoimmunity

Answer 9

Goodpasture syndrome, myasthenia gravis

Question 10

What is immune complex autoimmunity?

Answer 10

Antigen-antibody/immune complex formation and deposition, activating phagocytes, causing damage

TYPE 3 Hypersensitivity reaction

Question 11

What is SLE?

Answer 11

Failure of tolerance. allowing self reactive B and T Cells to circulate leading to DNA complexes which cannot be picked up by macrophages which then deposit in tissues where complement is activated = inflammation

Question 12

What form of collagen is damaged in Goodpasture’s?

Answer 12

Type 4

Question 13

What is the ratio of M:F in autoimmune disease?

Answer 13

1:4

Question 14

what induces tolerance?

Answer 14

tolerogens

Question 15

how is tolerance maintained?

Answer 15

Diversity of T-cell antigen receptors and immunoglobulin molecules.
Many antigen-specific receptors capable of binding to self-molecules.
To avoid autoimmune disease, the T and B cells bearing self-reactive molecules must be eliminated or downregulated.

Question 16

How is peripheral tolerance achieved?

Answer 16

Mature lymphocytes that recognize self antigens in peripheral tissues become incapable of activation or die by apoptosis

Question 17

What are the mechanisms of peripheral tolerance?

Answer 17

Anergy - functional unresponsiveness

• Antigen recognition without co-stimulation
• Treg suppression
• Deletion

Question 18

How do you overcome peripheral tolerance ?

Answer 18

Inappropriate access of self-antigens/increased local expression of co-stimultory molecules

Alterations in which self molecules are presented to the immune system

Question 19

When are you most likely to overcome peripheral tolerance?

Answer 19

During periods of inflammation

Question 20

What kind of hypersensitivity reactions occur during autoimmunity?

Answer 20

types II, III, IV