10: Major Histocompatibility Complex Flashcards
Polygenic
several genes exist for a given MHC class
Polymorphic
a large number of alleles exist for a given gene
Promiscuous
will bind a range of similar epitopes
MHC Class I
single chain, presents endogenous Ag to CD8+ T cells (cytotoxic T cells)
MHC Class II
2 chains, presents exogenous Ag to CD4+ T cells (helper T cells)
MHC Class III
encode cytokines, heat shock proteins, Ag processing and transport proteins, and complement proteins
How to MHC molecules bind the epitope on cell surface?
electrostatically
How is the MHC single chain associated with beta 2-microglobulin?
non-covalently
What type of cells are involved in MHC class I?
virus-infected cells and tumor cells
What cells express MHC class I molecules?
every nucleated cell
What cells express MHC class II molecules?
primarily WBCs
What does the thymic epithelium mostly express?
MHC class II molecules