Immunology: Cellular Components

Question 1

Difference between MHC 1 and MHC 2

Answer 1

MHC 1:
- includes the following loci:
HLA-A/B/C
- bind to TCR and CD 8 receptors on all nucleated cells, APCs and platelets
- present primarily to cytotoxic T-cells (CD-8 T-cells)
- use RER and TAP proteins for antigen peptide loading
has 1 long and 1 short chain
- long chain = a2/a3 sub-chains
- short chain = a1/B2 sub-chains
“MHC-1 loci have 1 letter”

MHC:2
- includes the following loci: 
HLA-DP/DQ/DR
- bind to TCR and CD 4 receptors 
- present primarily to CD-4 helper T-cells 
- use invariant chain to antigen load 
- has 2 equal length chains with 2a/2b subchains
“ MHC-2 loci have 2 letters