Innate to adaptive Flashcards
1
Q
How many alleles code for MHC molecules?
A
Polymorphic - 9 alleles on chromosome 6
2
Q
Alleles that code for MHC are on which chromosome?
A
Chromosome 6
3
Q
What kind of inheritence for MHC molecules
A
Codominant
4
Q
Which cells express MHCI molecules?
A
All nucleated cells (NOT RBC)
5
Q
Which cells express MHCII molecules?
A
ONLY PROFESSIONAL APCs
- DC essential for primary T cell response
- macrophages & B cells augments pre-existing immune response
6
Q
How are MHCI-peptide complexes synthesised?
A
- Viral proteins are ubiquinated and broken down by proteasomes into peptides.
- Peptide are transported to ER via TAP proteins
- MHC I folds with peptides and is transported to GA
- Fuse with plasma membrane
7
Q
How are MHCII-peptide complexes synthesised?
A
- 2 chains of MHCII molecules are synthesised in the ER and binds to an invariant chain, preventing binding of intracellular pathogens.
- This complex is transported to the GA and then into endosomes containing extracellular pathogens.
- In the endosomes, invariant chain on MHC II molecules is processed into CLIP peptide, which is then replaced by antigenic peptides.
- Final MHC II-peptide complexes are then presented on cell surface to CD4 T cells.