CSIM - 1.57 - Autoimmunity 1 Flashcards
In basic terms how do auto-immune diseases arise?
Breakdown in tolerance
Where and how does central T-cell tolerance take place?
Thymus
Tissue specific Ag (AIRE genes) are tested with the maturing T-cells, if any react they are subsequently apoptosed
What can having auto-antibody against IgG lead to?
Rheumatoid factor
Which sites within the body are immune privileged?
Brain
Eyes
Testes
Uterus
Which sequestered Ag do not have central tolerance checked against them?
DNA
Sperm
Eyes
What type of cell is diabetes dependent upon?
T-helper cells
What type of cell is psoriasis dependent upon?
Th17 cells
Name the islets of Langerhan and their secretions?
alpha-cell - Glucagon
Beta-cell - Insulin
delta cell - Somatostatin
Describe how type 1 diabetes occurs?
Effector T-cells recognises peptides on Beta islets of Langerhan and kills the Beta-cell
No insulin is therefore made
Name the two types of T-regulatory cells and describe their functions?
Natural T-reg cell - secretes FOXP3 which inhibits self-Ag T-cells
Induced T-reg - peripheral tissues recognises Ag on immature dendritic cells
Which cytokine defects may give arise to SLE?
Over-expression of IFN-Y
Under-expression of TNF-a
AIRE gene deficiency may lead to which condition?
Chronic mucocutaneous cadadidiasis
What is IPEX syndrome?
FOXP3 (natural T-reg) mutation leading to severe GI disease
What is ALP syndrome?
FAS and FAS-L mutations - important in signalling apoptosis leading to huge lymphadenopathy
A mutation of the MHC gene - HLA-B27 leads to which condition(s)?
Ankylosing spondylitis
Acute anterior uveitis
A mutation of the MHC gene - HLA-DR2 leads to which condition(s)?
Multiple sclerosis
Goodpasture’s syndrome
A mutation of the MHC gene - HLA-DR3 leads to which condition(s)?
Grave’s disease
Myesthenia gravis
SLE
Type 1 diabetes
A mutation of the MHC gene - HLA-DR4 leads to which condition(s)?
Rheumatoid arthritis
Pephigus vulgaris
A mutation of the MHC gene - HLA-DR5leads to which condition(s)?
Hashimoto’s thyroiditis
Describe Crohn’s disease?
Inflammed bowel from an over-responsiveness to normal gut flora by abnormal Th1 and Th17 cells
Which hypersensitivity reaction gives arise to haemolytic anaemia?
Type 2 - antibody (IgG) against cell surface/matrix
Which hypersensitivity reaction gives arise to type.1 diabetes/multiple sclerosis/Chron’s disease?
Type 4 - cell mediated
Which hypersensitivity reaction gives arise to rheumatoid arthritis?
Type 3 - IgG immune complexes (activating complement)
Name 5 organ SPECIFIC autoimmune diseases?
Type 1 diabetes Good Pasture's syndrome Multiple sclerosis Chron's disease Grave's disease
Name 4 SYSTEMIC autoimmune diseases?
Rheumatoid arthritis
Scleroderma
SLE
Primary Sjogren’s syndrome
