Presentation of Self-Peptides: Consequences for Self Nonself Discrimination and Allorecognition

Abstract

For T cells, “self” is defined by the set of peptides presented on self MHC molecules at concentrations sufficient to trigger a T cell Response. A key feature of MHC molecules is their high degree of polymorphism and in the last years it has become increasingly clear that different allelic forms have different peptide specificities. Thus the set of self peptides presented (i.e., “self”) depends on the allelic form of MHC molecules. We want to discuss here the consequences of MHC polymorphism on presentation of self peptides.

Key Words:

• alloreactivity
• epitope
• HLA-DR
• polymorphism
• T cell