Immunology 1A: Autoimmune and auto-inflammatory diseases 2 Flashcards
Which antibodies do systemic diseases produce?
ANA
Graves’ disease pathophysiology
IgG antibodies to TSH receptor –> uncontrolled production of thyroid hormones which cannot be overrided by negative feedback
What kind of hypersensitivity is Grave’s?
Type II
Which thyroiditis is associated with a high T4 and which with low?
High; Viral thyroiditis (de quervain’s)
Low: Hashimoto’s thyroiditis
clinical features of hashimoto’s
Constipation, lethargy cold intolerance etc
GOITRE - irregular
Autoantibody in Hashimoto’s
anti-TPO and anti-thyroglobulin
Why is it not useful to measure autoantibodies in Hashimotos?
They are present in many women who do not exhibit any symptoms
Hypersensitivtiy type of Hashimoto’s
Type II and IV
Pathophysiology of T1DM? Therefore what hypersensitivity is it?
CD8+ T cells recognise autoantigens on pancreatic B cells
Type IV-mediated
On 1st presentation of T1DM, what else do you screen for?
Coeliac’s, TFTs and LFTs
What autoantigens are recognised by T cells in T1DM?
GAD and IA2
Antibodies seen in T1DM (often predate symptoms but not used diagnostically)
Anti-GAD
Anti-islet cell
anti-insulin
anti-IA2
Clinical fx of B12 deficiency
Subacute degeneration of cord
Optic neuropahty
Peripheral neuropathy
Pernicious anaemia autoantibodies
Autoantibodies to gastric parietal cells and intrinsic factor
Myasthenia gravis autoantibodies
Autoantibodies to ACh receptor
Special test for diagnosis
Tensilon test
MG type of hypersensitivity?
Type II
Offending antibody in Goodpasture’s
antibody vs alpha3 subunit of type IV collagen
Immunohistochemistry for anti-GBM, what is a +ve result?
Linear IgG deposition along basement membrane
What is seen on biopsy in GBM?
Cresentic nephritis
Goodpasture’s hypersensitivity
Type II
Rheumatoid arthritis HLA ASSOCIATIONS
HLADR4/HLADR1 (Bind to citrullinated peptides with higher affinity)
Which is the most SPECIFIC autoantibody in RA?
Anti-CCP
2 GENETIC predispositions to RA?
HLAdR4/DR1
PAD2 + 4 polymorphisms (deamination of arginine to citrulline)
What infection is associated with RA and why?
Porphyromonas gingivalis - expresses PAD enzyme thus promoting citrullination
Why does smoking increase RA risk?
Erosion and increased citrullination
What is rheumatoid factor
IgM antibody targeted against Fc region of IgG antibody