Autoimmunity

Question 1

What is immune tolerances

Answer 1

A state of unresponsiveness of the immune system to self

Question 2

What is central tolerance

Answer 2

Thymus eliminates T cells with high affinity to self-antigens

And Bone marrow in B cell tolerance

Question 3

What is peripheral tolerance

Answer 3

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

mechanisms:
Anergy,
Antigen recognition without co-stimulation 
Trey suppression 
Deletion

Question 4

What is autoimmunity

Answer 4

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

Physiological auto recognition with secondary epiphenomena

Autoimmune diseases occur when autoreactive T cells or autoantibodies cause tissue damage through hypersensitivity reactions type 2-4

Question 5

What causes autoimmunity

Answer 5

Unknown 
Immune regulation 
Hormonal 
Environment (infections, drugs, UV radiation)
Genetic factors (commonly polymorphisms)

Question 6

What is an autoimmune disease

Answer 6

Immune response contributing directly to tissue/ organ damage

Question 7

Whose more likely to get an autoimmune disease

Answer 7

Females

Question 8

Types of autoimmune diseases

Answer 8

Organ specific (anti-GAD) (eg endocrine)
Non-organ specific (ANA)

Question 9

Causes of autoimmune diseases

Answer 9

Cell mediated
Antibody mediated
Mixed/atypical reactions

Question 10

Types of cell mediated autoimmune disease?

Answer 10

Type 1 DM-autoreactive T cells against pancreatic islet cell antigens

Crohn’s disease- triggered by foreign pathogen leading to APC presentation and autoreactive T cells against intestinal floral antigens (can be familial)

Psoriasis- autoreactive T cells against skin associated antigens

Question 11

What is antibody medicated autoimmunity and examples?

Answer 11

Type 2 hypersensitivity (Ab binds to target leading to damage to Fc receptor macrophages)

Goodpasture syndrome
Myasthenia gravies
SLE (type 3 immune complex autoimmunity)

Question 12

Examples of mixed/ atypical autoimmune reactions

Answer 12

Graves diseases 
Molecular mimicry (eg group A strepcoccal M protein similar structure to antigen in cardiac muscle and can thus result in rheumatic fever)

Question 13

Cell mediated, antibody mediated, mixed/atypical reactions

All in one examples

Answer 13

MS

Question 14

What HLA subtype is most associated with Ankylosing spondylitis

Answer 14

B27

Question 15

What famial gene is inflammatory bowel disease most associated with?

Answer 15

NOD2