Flashcards in MHC and transplantation Deck (20):
Normal individuals have naturally occurring anti-A or anti-B __________.
______________ staining has revealed blood group substance in the cell membranes of all vascular endothelial cells, and certain epithelial cells.
Proteins encoded by the MHC are expressed at the cell surface and function to present ‘____’ and ‘_____’ antigens for inspection by _____ antigen receptors.
Proteins encoded by the MHC are expressed at the cell surface and function to present ‘self’ and ‘nonself’ antigens for inspection by T cell antigen receptors.
How many MHC molecules are on the average mammalian cell?
50,000 – 100,000 MHC molecules
What does MHC have an important role in?
Important role in immune function, disease susceptibility and reproductive success.
What does the class I region encode?
HLA-A, B, C (‘classical’) antigens
What does the class II region encode?
HLA-DR, DQ, DP antigens
What does the class III region encode?
HSP70, TNF, C4A, C4B, C2, BF, CYP21
How many kb make up the class I genes?
How many kb make up the class II genes?
What does HLA stand for?
Human Leucocyte Antigens
Where are class I antigens found?
all nucleated cells
Where are class II antigens found?
primarily expressed on B lymphocytes but expression can be induced on T lymphocytes and other cells
What does co-dominant expression mean for the antigens?
All of the inherited antigens are displayed on the cell surface (HLA phenotype).
MHC is highly polymorphic which means...
...there are a large number of allelic variants at each locus.
How is the allelic variation maintained at population level?
How is HLA polymorphism significant?
In terms of capacity of individual to mount an immune response in response to an antigenic challenge
What are the 3 types of recognition in grafts?
What is sensitisation?
Any event which elicits an HLA directed immune response