L9 Flashcards
what are the basic components needed for CD4+ t cell activation?
CD4+ T cell
antigen
antigen-presenting cell (dendritic cell)
there are resident ____ in lymph node paracortext all the time
dendritic cells
the resident DC can capture and present ____ draining into lymph nodes from the tissue via lymphatics
antiens
to fully activate a t cell you need a ____
second signall
DCs recognize pathogen assocaited molecules via ___
PRRs
pattern recognition receptors
what happens if a t cell recognizes an antigen but doesn’t get co-stimulated?
it becomes anergic - unresponsive to anitgen
this is a good way of stopping t-cells getting activated by self-antigen
to achieve CD4+ t cell acitvation, you need
recongition of antigen presented by MHCII
and a co stimulatory signal
DCs are specialized to provide signal ___-
2
signal 1 in the absnese of signal 2 makes t-cell ____
anergic
_____ events are important in supporting t-cell activation
cell-adhesion
ICAM-1 is an important ___ molecule
cell adhesion
what does ICAM-1 LFA-1 interaction allow?
allows t cells to come into close contact with DCs to sample antigens
immunological synapse
interactions between CD4+ t cells and DC at point of contact which is known as ^^
clusters of molecules at T-cell-DC interface are called
supramolecular activation clusters (SMACs)