Session 3: Autoimmunity Flashcards
Define autoimmunity.
Immune response against the host due to the loss of immunological tolerance of self-antigen.
The host should not react but it does for some reason.
Define autoimmune disease.
Disease caused by tissue damage or disturbed physiological response due to an autoimmune response.
Classifications of autoimmune disease.
Organ specific
Non-organ specific
Explain organ specific autoimmune disease.
One or multiple self antigens within one single organ or tissue.
Explain non-organ specific autoimmune disease.
Wide distributed self antigens throughout the body causing problems.
Give examples of organ specific autoimmune diseases.
Hashimoto’s
T1DM
MS
Anti-GBM syndrome
Addison’s
Graves’
Myasthenia gravis
Pernicious anaemia
Give examples of non-organ specific autoimmune diseases.
Autoimmune haemolytic anaemia
RA
SLE
Sjogren’s syndrome
Autoimmune thrombocytopenic purpura
What are the different autoimmune disease drivers?
It can be autoantibody driven or autoreactive T cell driven.
Primary Autoantibody in Graves’
Anti-TSHR (e.g. TSI)
Primary Autoantibody in Myasthenia gravis
Anti-acetylcholine receptor
Primary Autoantibody in Anti-GBM syndrome
Anti-anti-Glomerular basement membrane
Secondary autoantibody in SLE
Anti-nuclear
Secondary autoantibody in pernicious anaemia.
Anti-gastric parietal cell
Secondary autoantibody in hashimoto thyroiditis
Anti-thyroid peroxidase antibodies (E.g. Anti-TPO)
Secondary autoantibody in RA
Anti-rheumatoid factor
Set of criteria for the diagnosis of a disease as autoimmune.
Presence of autoantibodies/autoreactive T cells
Autoantibodies/autoreactive T cells found at the site of tissue damage
Transfer of auto-antibody or autoreactive T cells to a healthy host will induce the autoimmune disease.
Clinical benefit is provided by immunomodulatory therapy
FH
How does levels of auto-antibodies relate with disease severity.
Positively linear.
More autoantibodies -> more severe disease.
What triggers autoimmunity?
Genetic factors such as family history (sibling and identical twins makes it more common) and also mutations.
Environmental factors
Give examples of environmental factors that can trigger autoimmune disease.
Hormones
Infections
Drugs
What infection causes rheumatic fever?
Streptococcus pyogenes M protein with an antigen in cardiac muscle.
What infection can cause Guillain-Barré syndrome?
Campylobacter jejuni glycoproteins with myelin-associated gangliosides.
What infection can cause T1DM?
Coxsakieviruse B4 nuclear protein
D-penicillamine is a drug given sometimes for RA.
What autoimmune diseases can they cause?
Myasthenia gravis
Pemphigus
SLE
Glomerulonephritis
