Revealing the hidden self : Molecular mechanism for immune surveillance

“Effective immune surveillance requires cells to display their intracellular proteins in the form of peptides on the cell surface.  The peptides are produced by selectively fragmenting proteins in the cytoplasm.  The peptide mixture is transported into intracellular compartments for further trimming by resident proteases.  Suitable peptides are loaded on the major histocompatibility complex (MHC) molecules that carry the peptides to the cell surface.  The peptides on the cell surface are surveyed by specialized “killer” cells of the immune system.  If a peptide derived from an intracellular virus is found, the killer cells eliminate the infected cell.  I will discuss the peptide display mechanism, called antigen presentation, and its unexpected implications for genomics, immunity and vaccines.”