Antigen Processing And Presentation

Question 1

MCH Class I

Answer 1

• Presents to CD8 T cells
• Alerts T cells to intracellular infections
• Expressed on all cells
• Viruses

Question 2

MHC Class II

Answer 2

• Presents to CD4 T cells
• Alerts T cells to extracellular infections
• Expressed on dendritic cells, B cells and macrophages
• Bacteria

Question 3

Describe the structure of MHC Class I

Answer 3

Single transmembrane chain divided into 3 segments with a beta-microglobulin to stabilise.

Question 4

Describe the structure of MHC Class II

Answer 4

2 transmembrane chains with 2 domains on each.

Question 5

Describe the process of peptide binding to MHC Class I

Answer 5

Peptide transported from cytosol to lumen of ER by TAP.

2 subunit of MHC form a binding site and it stabilised by calnexin until beta microglobulin arrives.

Calnexin is released and peptide is delivered to MHC by TAP.

MHC is exported from ER and ERAP cuts the peptide if it’s too long.

Question 6

Name the classes of MHC

Answer 6

MHC Class I

MHC Class II