autoimmunity Flashcards
what is the most prevelent immune cpmplex disease
SLE
autoantibodies to what are produced in SLE
nucleic acids
what is low in sle patients
C3 and C4
why are c3 and c4 low in sle patients
immune complexes bind them and serum IgG is elevated beccause of the expanded b cell pop
how do t cells injure tissue
by triggering DTH reactions or by directly killing target cells
what causes DTH responses
CD4 TH1 cells and CD8 t cells
killing of cells can occur through
cd8 ctls recognition of peptide/class 1 MHC complexes
DTH reactions
injury results from products of activated macrophages such as lysosmal enzymes, reactive oxygen species, nitric oxide and inflammatory cyokines
chronic DTH leads to
fibrosis as a result of cytokines produced by macrophages
organ specific autoimmune diseases are caused by
DTH reactions produced by autoreactive T cells
type 1 diabetes results from
destruction of insulin producing b cells in the islets of langerhns in the pancreas
what is the most common neurological disease in young adults
MS
produce autoreactive t cells that form inflammatory lesions along the myelin sheath of nerve fibers
MS patients
the csf of ms patients
contains activated t cells that infiltrate the brain
autoimmunity results from
a failure or breakdwon of the mechanisms responsible for maintaing self tollerance of be and t cellsn
epitope spreading
self antigen that injure tissues may reslut in the release or alteration of other antigens and activation of lymphocytes specific for those antigens worsening the diesase
most autoimmune diseases are
polygenic
class 1 hlA B27
ANKLOSING SPONDYLTITS
PTPN22
a gain of function variant of a protein phosphatase that results in weak T and B cell receptor signaling and could cause defects in peripheral tolerance
CD25 IL2RA
polymorphisms affecting the expression of cd25 are associated with ms
il-23r
defects could affect th17 responses to micrboes causing intestinal or cutaneous inflammation
mechanism of central tolerance
AIRE
generation of regulatory t cells
FOXP3 IL-2
polymorphisms in the inhibitory FcyRIIB are associated with
SLE
deficiency in genes encoding complement proteins are associated with
lupus like diseases
aire
destruction of endocrine organs by antibodies lymphocytes
oral tollerance
systemic adaptive immune tolerance to antigens that are ingested and may be a way of treating autoimmune diseases
il-10 function
il 10 inhibits the production of IL-12 by activating dendritic cells and macrophages
what is least likely to be involved in lymphocyte homeostasis
CD28
CD28 binds to what
B7
high doses of antigens favor
thymic deletion
infections can promote the development of autoimmunity by what mechanism
molecular micmcry
what is immunological tolerance
unresponsiveness of the immune system to an antigen which is induced by previous exposure to that antigen
what is a mechanism for central tolerance of b cells and not t cells
receptor editing
a genetic deficienvy in the ability to produce what molecules results in autoimmunity
IL-2
