Tolerance and Autoimmunity Flashcards
What immunologic tolerance
the ability to ignore “self” while reacting to “non-self”
Where does central tolerance take place
thymus and bone marrow
Where does peripheral tolerance take place
spleen, lymph node and non-lymphoid tissue
What are the central tolerance mechanisms for T cells
positive/negative selection
What are the central tolerance mechanisms for B cells
clonal deletion, anergy, receptor editing
What do thymic epithelia cells express, what do they do
AIRE, regulate expression of hundred of tissue specific self antigen
What happens to high affintiy, self-antigen specific CD4+ T cells
they become Treg cells with regulatory function
What is the gene that is the master regulator for Tregs
Foxp3
What induces death
Fas/FasL
What are inducible Treg cells, what is the difference between this and other T regs
generated from Th0 cells in presense of immunomodulatory cytokines (TGF-beta, IFN-gamma, IL-10), not contact dependent
T/F: Autoimmune diseases are usually by multiple gene defects
True
What are gene defects that will cause single gene defects
Fas/FasL, AIRE, Foxp3