Immunology 5 - Autoinflammatory and autoimmune disorders Flashcards
What is the difference between auto-immune and auto-inflammatory diseases?
Auto-inflammatory involves innate immune system
Auto-immune involves adaptive immune system
Which type of cell can produce IL1 and NFkappaB?
Neutrophil
What is the role of cryopyrin in inflammation?
Induces IL1/NFkB secretion by neutrophils
What is the role of pyrin-marenostin in inflammation?
Inhibits IL1/NFkB secretion by neutrophils
What is the inheritance pattern of Familial Mediterannean Fever?
Autosomal recessive
What is the mutation that causes Familial Mediterannean Fever?
MEFV mutation - this is the gene that codes Pyrin-marenostrin (inhibitory of inflammation)
Cryopyrin therefore not opposed
What are the symptoms of Familial Mediterannean Fever?
Periodic fevers of about 2-3 days duration
Pleurisy
Arthritis
Rash
What is the long-term risk of Familial Mediterannean Fever?
AA amyloidosis
What is the treatment for Familial Mediterannean Fever?
Colchicine
This binds tubulin on neutrophils
What is TRAPS?
TNF-Receptor Associated Periodic Syndrome
What is the defect that causes APECED?
AIRE
- -> Defect in T cell tolerance
- -> autoreactive T cells
What does APECED stand for?
Autoimmune PolyEndocrinopathy Cabndidiasis Ectodermal Dystrophy
What is the role of AIRE?
Upregulates expression of self antigen by the thymus to promote T cell apoptosis
What are the symptoms of APECED?
Auto-immune diseases - mostly hypoparathyroidism and Addisson’s
What is the pathophysiology of candida susceptibility in APECED?
Auto-antibodies vs IL17 and IL22 are produced, which are interleukins that are important in candida immunity
What does IPEX stand for?
Immune polyendocrinopathy enteropathy X-linked syndrome
What is the mutation that causes IPEX?
FOXP3
What is the usual role of FOXP3?
Required for T reg cell development and function
What is the pathophysiology of IPEX?
FOXP3 mutation –> failure to negatively regulate T cell responses –> lots of autoreactive B cells
What are the symptoms of IPEX?
Diarrhoea, Diabetes, Dermatitis
What does ALPS stand for?
Autoimmune Lympho Proliferative Syndrome
What mutation causes ALPS?
Fas pathway mutation
What are the symptoms of ALPS?
Defect in lymphocyte apoptosis –> splenomegaly and lymphadenopathy
Autoimmune cytopaenias
Lymphoma
Recall 2 mutations associated with Crohn’s disease
IBD1
NOD2
What is the HLA association of ankylosing spondylitis?
HLA-B27
Where in the body is most affected by ankylosing spondylitis?
Areas where there are high tensile forces
Recall 2 genetic associations of Grave’s disease
HLA-DR3
CTLA4
Recall 3 genetic associations of SLE
HLA-DR3
CTLA4
PTPN22
What is the HLA association of Rheumatoid Arthritis?
HLA-DR4
What is the HLA association of Goodpasture’s disease?
HLA-DR15
Recall the Gel and Coombs classification of hypersensitivity
Type 1: immediate and IgE mediated
Type 2: Antibody to cellular angtigen mediated
Type 3: Immune complex mediated
Type 4: Delayed type - T cell mediated
Recall 4 type 2 hypersensitivity diseases
Grave’s
Goodpasture’s
Pemphigus
Myasthaenia
Against what is the auto-antibody directed in Goodpasture’s disease?
Non-collagenous domain of type 4 collagen in the basement membrane
Against what is the auto-antibody directed in pemphigus vulgaris?
Cadherin
Against what is the auto-antibody directed in Grave’s?
TSH receptor (stimulating)
Against what is the auto-antibody directed in myasthaenia gravis?
Acetylcholine receptor
Recall 2 examples of type 3 hypersensitivity disorders
SLE
Rheumatoid arthritis
What is rheumatoid factor?
Antibody directed against the Fc portion of IgG
Mutations in which enzymes are associated with rheumatoid arthritis and why?
PAD enzymes - these are involved in citrullinisation
How can you test for anti-nuclear antibody (ANA)?
Stain Hep-2 cells with fluorescent stain
Which antibody is most specific for SLE?
Anti-dsDNA
Recall the expected C3 and C4 levels in active vs severe SLE
Active: low C4, normal C3
Severe: both low
Which antibody tests should be done to investigate anti-phospholipid syndrome?
- Lupus anti-coagulant
- Anti-cardiolipin
- Anti-beta 2 glycoprotein 1
What are the 2 types of systemic sclerosis?
CREST (limited cutaneous systemic sclerosis)
Diffused cutaneous systemic sclerosis
What is the autoantibody involved in CREST?
Anti-centromere
What is the autoantibody involved in diffuse cutaneous systemic sclerosis?
Anti-topoisomerase (Scl70)
What are the symptoms of CREST?
Calcinosis Raynaud's Esophageal dysmotility Sclerodactyly Telangiectasia PLUS PRIMARY PULMONARY HTN (important)
What are the symptoms of diffuse cutaneous systemic sclerosis?
Same as CREST, but additionally:
- More GI disease
- Interstitial lung disease
- Renal crisis
What are the 2 forms of idiopathic inflammatory myopathy?
Dermatomyositis
Polymyositis
What is the phrase “helicopter rash” pathognemonic for?
Dermatomyositis
Recall 2 symptoms of dermatoyositis
Rash
Proximal myopathy
What is the main symptom of polymyositis?
Proximal myopathy
What is the main autoantibody association of small vessel systemic vasculitides?
ANCA
Recall 3 examples of small vessel systemic vasculitides
- Microscopic polyangiitis
- Granulomatosis with polyangiitis
- Eosinophilic granulomatosis with poly-angiitis
Which of the small vessel vasculitides is associated with cANCA?
Granulomatosis with polyangiitis (previously Wegener’s)
Which of the small vessel vasculitides is associated with pANCA?
Microscopic polyangiitis
Eosinophillic granulomatosis with polyangiitis (previously Churg Strauss)
What is cANCA?
Antibody to proteinase 3
What is pANCA?
Antibody to myeloperoxidase