Immune Tolerance Flashcards
What is central tolerance and what are the mechanisms?
Immunological tolerance to self antigens induced in immature lymphocytes. Done through deletion, receptor editing, development of regulatory T cells.
What is peripheral tolerance and what are the mechanisms?
Immune tolerance to self antigens in peripheral tissues encountered by mature lymphocytes. Done through Colonal anergy, Deletion, and Suppression through TReg secreted IL and TGF.
What is Type II HS mediated by and what are the mechanisms?
IgG and IgM bind to Ags. Results in Cytotoxicity through complement lysis, inflammatory cell injury, and phagocytosis.
What is Type III HS mediated by?
Failure of immune complex removal resulting in inflammation.
What is the target antigen, mechanism, and manifistation of Graves disease?
T: TSH receptor
Me: Ab-mediated stimulation of TSH receptors.
Ma: hyperthyroidism.
What is the target antigen, mechanism, and manifestation of Myasthenia gravis?
T: Ach receptor
Me: Ab inhibits Ach binding
Ma: Muscle weakness and paralysis.
What is the mechanisms of tissue injury in autoimmune diseases like Type 1 diabetes, RA or MS?
It is T cell mediated by Th cells via DTH.
WHat is the mechanism of induction of antibodies by cross-reactive antigens?
Similarities between a self antigen and foreign antigen can cause a cross-reaction, where Th and B cells react to the foreign antigen but then autoreact.
What is the mechanism of periodontitis and what autoimmune disease can it trigger?
Infection generates protein citrullination, with antibodies created against CCPs. CCPs are found in synovial fluid, and these abs now attack them, leading to Rheumatoid arthritis.
