T Cells & Antigen Presentation Flashcards
What are the 4 interactions in the primary response?
- antigen–DC
- DC–T cell
- antigen–B cell
- T cell–B cell
What cell’s express MHC class II?
- DC
- B cell
- macrophages
What do mature DCs upregulate?
B7
Where are B and T cells presented to?
SLT
What 3 interactions are required when DCs present to T cells?
- TCR–MHC
- CD4/CD8
- CD28–B7
What 3 interactions are required when B cells present to T cells?
- MHC—TCR
- CD40–CD40L
- CD4/8
What are the 2 fates of B cells after forming a conjugate pair with T cells in the SLT?
- become a memory B cell and express IgM
- undergo SHM and class switching and become a plasma cell that secretes IgA, G, E
What cell type is inactive in secondary immune response?
naive B cells (not specific)
What is central tolerance?
T cell development and selection
What are 3 outcomes of Treg–MHC interaction?
- increased IL-10
- increased CTLA-4
- increased IL-2R
- linked expression
What are the steps of central tolerance?
- HPSC
- blood
- thymus cortex
- double negative
- positive selection
- double positive
- thymus medulla
- negative selection
- single positive
- blood
What presents to T cells in positive selection?
cTECs
What presents to T cells in negative selection?
AIRE+ mTECs
What allows single positive T cells out of the thymus and into the blood?
S1P
How does FTY720 (anti-S1P) prevent auto-reactive T cells?
prevents them from leaving the thymus
