Flashcards in 13 MHC and transplantation Deck (10)
How many MHC molecules are there on the average mammalian cell?
Where on the chromosome is the HLA complex?
The HLA complex has three regions, which antigens does each encode?
1: HLA-A/ B/ C
2: HLA-DR/ DQ/ DP
3: HSP70, TNF, C4A, C4B, C2, BF, CYP21
The two classes of antigens are found on different cells, which is where?
1: all nucleated cells
2: B lymphocytes (may be induced on T lymphocytes)
The two classes of antigens have different structures - distinguish between them.
1: 45kd heavy chain and B2 microblobulin
2: 31kd a chain and 26kd B chain
How is the HLA complex inherited?
En-bloc from each parental chromosome. Codominant expression - all inherited antigens are displayed (HLA phenotype).
What is the difference between direct and indirect MHC recognition?
Direct: white blood cells from donor present directly to recipient T cells.
Indirect: foreign proteins are broken down and presented to T cells by MHCII of self APC's
What is sensitisation? Name three examples.
Any event which elicits an HLA directed immune response.
Pregnancy, blood transfusion, transplantation.
How are the chances of an organ transplant determined by immunologically?