Tolerance And Autoimmunity Flashcards
absence of specific immune response against some
antigens in an otherwise immunocompetent person
Tolerance
T/F: Auto tolerance is natural
True
T/F: Acquired tolerance can be used to treat autoimmune
diseases, allergy & graft rejection.
True
Location of colonal deletion
In central lymphoid organs
T/F: Immature T cells that recognize self antigen die through apoptosis ( negative selection).
False
- Immature T cells that recognize self peptide plus self MHC at
high affinity die through apoptosis ( negative selection).
How are self reactive B cells controlled In peripheral tissue ?
Lack of help from T cells (th)
How are self reactive T cells controlled in the peripheral tissue ?
Lack of co-stimulation = anergy
Breakdown of auto tolerance causes
Auto immune disease
Class II MHC are normally expressed ONLY on :
APC
What increases the expression of MHC II on a variety of cells ?
IFN-gamma
M-protein of some strains of Streptococcus pyogenes
share epitopes with
The heart muscle antigens
Cross reactivity against streptococcus pyrogens can cause what diseases ?
Rheumatic fever and rheumatic heart disease
Microbe that causes polyclonal activation of lymphocytes :
Epstein Barr virus (EBV)
Probable cause for the genetic factor in autoimmune diseases ?
particular
MHC (HLA) types ,
MHC type responsible for SLE
DR3
