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All the peptides that fit: the beginning, the middle, and the end of the MHC class I antigen-processing pathway

Nilabh Shastri1, Sylvain Cardinaud, Susan R Schwab

  • 1Department of Molecular and Cell Biology, Division of Immunology, University of California, Berkeley, CA 94720, USA. nshastri@socrates.berkeley.edu

Immunological Reviews
|September 27, 2005
PubMed

The end result of the antigen-processing pathway is the display of peptide-bound major histocompatibility complex I (pMHC I) molecules. The pMHC I molecules are expressed on the cell surface where they can be surveyed by CD8(+) T cells for abnormal proteins. MHC I molecules present a large repertoire of peptides that fit perfectly in their binding grooves and represent the otherwise hidden intracellular contents. Many peptides originate as defective ribosomal products in the cytoplasm. In a stepwise manner, the antigen-processing pathway generates and protects the proteolytic intermediates until they yield the final peptides that can fit the MHC I in the endoplasmic reticulum.

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