Immunology Flashcards
(25 cards)
Which chromosome do you find HLA on?
Chromosome 6
What is HLA?
A locus of genes that encodes for the proteins on the surface of cells that regulate the immune response.
What do class 1 (A, B and C ) HLA molecules do?
Present peptides from within the cell (eg if the cell becomes infected with a virus it will bring fragments of the cell to the surface so that the cell can be recognised as infected and can be destroyed)
What do class 2 HLA molecules do?
Present antigens from outside the cell to the T lymphocytes. These antigens then stimulate multiplication of T helper cells which then stimulate antibody producing B cells to produces antibodies.
What suppresses self antigens?
Regulatory T cells
What does HLA class 3 do?
Encodes for the components of the complement system
What other autoimmune disease are associated with graves disease?
Hashimotos thyroiditis Autoimmun pernicious anaemia Addisons Vitiligo Myasthenia Gravis
What other autoimmume disease is associated with SLE?
Primary sjogrens
How does the damage occur in autoimmune diseases?
Circulating auto antibodies recruit other components of the immune response (complement, phagocytes, NK cells) to attack certain sites
What type of hypersensitivity reaction is SLE?
Type 3 (Immune complex mediated)
Describe briefly the pathophysiology of SLE
- Autoantibodies to cell nuclei produced (anti DNA, ANA and anti Ro/La)
- These then form immune complexes which are deposited in the small vessels in the skin, joints and kidneys.
- This then results in complement activation in this area and inflammation which leads to the recruitment of other cells.
What is a normal titre of ANA in a healthy person?
Less than 1:80
What conditions are anti Ro/La most specific for?
SLE and sjogrens
What auto antibody is most associated with scleroderma?
Anti centromere antibody
In what diseases would you expect to see Anti Jo -1 antibody?
Polymyositis, dermatomyositism polymyositis scleroderma.
What condition within an autoimmune disease is most associated with anti Jo 1 antibody?
Interstitial lung disease
What autoantibody is most associated with sjogrens?
Anti La
What autoimmune condition is most associated with ant RNP antibody?
Mixed connective tissue disease and SLE
What conditions is the anti Ro antibody specific for?
sjogrens, SLE
What disease is maternal anti RO antibodies associated with?
Neonatal lupus
What is Anti Sm antibody very specific for?
SLE
What disease is Anti Scl 70 associated with?
Diffuse scleroderma
Would you expect serum levels of C3 and C4 to be low or high in a patient with SLE? Why?
Low. C3 and C4 will be mostly deposited in tissues
What type of hypersensitivity reaction in rheumatoid arthritis?
Type 4
