2.4 - Autoimmune disorders Flashcards
(37 cards)
central tolerance in the thymus leads to either T cell apoptosis or ____________
generation of Treg cells
what is the result of an AIRE mutation? what is the normal function of AIRE?
- autoimmune polyendocrine syndrome
- controls the mechanisms that prevent the body from attacking itself
autoimmune polyendocrine syndrome is due to a mutation in _______
AIRE
what is the pathogenesis of autoimmune polyendocrine syndrome?
- mutation in AIRE
- failure of central tolerance (
where does positive selection of T cells occur?
cortex of thymus
where does negative selection of T cells occur?
medulla of thymus
the cortex of the thymus is where _______ selection of T cells occurs
positive
the medulla of the thymus is where __________ selection of T cells occurs
negative
what are the manifestations of autoimmune polyendocrine syndrome?
- hypoparathyroidism
- adrenal failure
- chronic candida infection
is autoimmune polyendocrine syndrome a failure of positive or negative selection?
negative (normally prevents body from making self reactive T cells)
peripheral tolerance leads to what two outcomes?
- anergy
- apoptosis of T and B cells
what condition results from a mutation in the Fas apoptosis pathway?
autoimmune lymphoproliferative syndrome (ALPS)
ALPS is a result of a mutation in what process?
Fas apoptosis pathway
what is the pathogenesis of autoimmune lymphoproliferative syndrome (ALPS)? what is the result?
- mutation in Fas apoptosis pathway
- self reactive lymphocytes cant undergo apoptosis and can generate IgG against blood cells, leading to lymphopenia
Treg cells block T cell activation and suppress autoimmunity by producing what cytokines?
IL-10 and TGFB
polymorphisms in what CD are associated with autoimmunity?
CD25
mutations in what gene lead to IPEX syndrome?
FOXP3
what is IPEX syndrome? what is cause?
- Immune dysregulation
- Polyendocrinopathy
- Enteropathy
- X linked
- due to FOXP3 mutation
what is the normal function of FOXP3?
“forkhead box P3”
involved in the development and function of Treg cells
what is the pathogeneis / cause of anti-nuclear antibodies seen in SLE? how does damage ensue?
- poorly cleared apoptotic debris (from UV light) activates self reactive lymphocytes, which then produce the antibodies
- DNA antigens activate TLRs, amplifying immune response (IFNa)
deficiencies of what complement proteins is associated with SLE?
C1q, C4, C2
what are the important antiphosphlipid antibodies seen in SLE?
- anticardioplipin
- anti-B2 micrglobulin I
- lupus anticoagulant
what antibody can lead to a falsely elevated PTT in SLE?
lupus anticoagulant (anti phospholipid Ab)
does antiphospholipid Ab syndrome lead to a hyper- or hypo- coagulable state?
hypercoagulable
