2.4 Flashcards
(41 cards)
how are T cells in lymphoid organs alerted when there is an infection
APC are captured and processed and the antigens are transported to T cells
antigens are transported from ___ to ___ where recognition by __ occurs
- tissue / mucosa
- lymphoid organs
- T cells
what resides in tissues and captures microbes and antigens
dendritic cells
___ are drained via lymphatic vessels or enter blood stream
cell-free antigens
the majority of DC in tissues and lymphoid organs are ___
classical DC
classical DC are in the ___
t cell zone of lymph nodes
___ capture and process protein antigens
immature dendritic cells
DC are activated via ___ and migrate to lymph nodes via ___
- PRR
- chemokine gradient
chemokine gradient is produced by the upregulation of ___ and ___
- chemokine receptors (CCR7)
- costimulatory molecules
___ present protein antigens to T cells
mature DC
what determine the specific recognition of antigens by T cells
major histocompatability complex (MHC) molecules
MHC molecules display ___ derived from ___
- peptides
- protein antigens
___ on T cells recognize ____ displayed by ___ on APC
- T cell receptors
- peptide antigens
- MHC molecules
what are human MHC proteins called
human leukocyte antigens (HLA)
what are the 2 sets of highly polymorphic genes
- Class I MHC genes
- Class II MHC genes
___ & ___ are susceptibility factors for periodontitis
- HLA-A9
- HLA-B15
what is the structure of MHC class I molecules
- membrane proteins containing a peptide-binding cleft at the amino-terminal
- alpha chain associated with beta 2 - microglobulin with a groove accomodating 8-9 aa peptide
what is the structure of MHC class II molecules
- membrane proteins containing a peptide-binding cleft at the amino terminal
- alpha & beta chains with a groove accomodating 10-30 aa peptide
CD8 T cells only recognize peptides presented by ___
MHC class I
how are peptides recognized by CD8 Tcells
the alpha 3 binds CD8 on CD8 Tcells
CD4 T cells only recognize peptides presented by ___
MHC class II
how are peptides recognized by CD4 T cells
beta 2 binds CD4 on CD4 T cells
what do MHC polymorphisms ensure
that a population can deal with microbe diversity
what are MHC class II expressed on & induced by
- APC
- IFN gamma