Flashcards in Lecture # 11 MHC Presents Peptide Antigen to T Cells: MHC Restriction Deck (11):
MHC I/MHC II
What is the role of polymorphism in MHC presentation?
Polymorphism contributes to the ability of the immune system to respond to many different and rapidly evolving pathogens (this makes it difficult for pathogens to evade presentation)
Class I alpha chain genes
HLA-A, HLA-B, HLA-C
Class II alpha and beta chain genes
HLA DQ, HLA-DR, HLA-DP
On what chromosome is b2microglobulin
Chromosome 15. Remember Class I MHC has one MHC encoded gene and one non-MHC encoded gene.
Class III MHC genes
Encode immune molecules: 1) Complement proteins (C4, Factor B, C2) 2) Cytokines: LTb, TNF-alpha, LT) Also encodes TAP
What are MHC haplotypes? How are they inherited? What kind of dominance do they show?
MHC haplotypes are the genetic makeup of one's MHC. They are inherited from parents and they are co-dominant.
A haplotype is a set of DNA variations, or polymorphisms, that tend to be inherited together. A haplotype can refer to a combination of alleles or to a set of single nucleotide polymorphisms (SNPs) found on the same chromosome.
Where are the polymorphisms in MHC?
Polymorphisms occur at peptide binding sites to accommodate different peptides.
Mouse Class I
H-2k, H-2D, H-2L