Major histocompatibility complex

Function

Major Histocompatibility Complex (MHC) are part of the cell immune system. MHC molecules display antigens on the host cell’s surface. T cell or natural killer receptors recognize the MHC:peptide and activate the immune response.

• MHC class I (Major Histocompatibility Complex Class I) are found in all nucleated cells. These cell surface proteins display peptides from cellular intrinsic proteins^[1]. For more details see
  
• Effect of HCMV on Major Histocompatibility Complex Class I
  
• MR1 Binds Vitamin Metabolites.
  
• MHC class II are found in professional antigen-presenting cells like macrophages. These cell surface proteins display peptides from cellular extrinsic proteins^[2].
  

For MHC class II interactions with T-cell receptor and gliadin peptide see SP3.4-TCR-HLA-DQ8-α-1-gliadin complex.

Structural highlights

. The ^[3]. Water molecules shown as red spheres.