14 - LINKING 5 Flashcards
Exceptions and MHC genetics
1
Q
what are the three exceptions to the rules
A
2
Q
what is cross presentation by dendritic cells and some examples
A
3
Q
what is the mechanism and function of cross presentation
A
- actual redirection mechanism is unclear
- dendritic cells need a “license”
–> DC can present foreign antigen to CD4+ helper T cell and get “licensed” to redirect exogenous Ag into the endogenous pathway from the T cell - “license”: cytokine and ligand signal between the APC/helper T cell
this allows for their presentation on MHC I, priming CD8+ T cell responses
need to have activated CD4+ T cell first to then license and cross present
4
Q
how does presentation of cytosolic peptides by MHC II molecules happen and some examples
A
5
Q
what is MHC restriction
A
6
Q
what is allorecognition
A
7
Q
what is direct allorecognition
A
8
Q
what is indirect allorecognition
A
9
Q
which genes encode for MHC molecules and where are they found
A
10
Q
what are the two classes of MHC genes
A
11
Q
what is the haplotype
A
12
Q
how are MHC alleles expressed
A
13
Q
how does polygeny result in a high degree of variance in MHC expression in the population
A
14
Q
how does allelic variation affect the peptide binding groove
A
15
Q
summary
A
