Accession Number : ADP008552

Title :   Possible Processing of Exogenously Added Synthetic Peptide by Cells Serving as Targets for a Cytotoxic T Lymphocyte Response,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE

Personal Author(s) : Tsomides, Theodore J. ; Eisen, Herman N.

Report Date : 1992

Pagination or Media Count : 4

Abstract : T-cells recognize peptide antigens at cell surfaces in association with self glycoproteins called MHC (major histocompatibility complex) proteins, leading to the term 'MHC-restriction'. T-cells expressing CD4 are restricted by class II MHC molecules, while T-cells expressing CD8 are restricted by class I MHC. For instance, viral or other antigenic peptides generated within cells associate with class I MHC molecules in the endoplasmic reticulum during assembly from their two component chains, alpha and Beta(Sub2)m, to form a heterotrimetric complex recognized by CD8(+) T-cells. Once at the Cell surface, Most class I molecules exist as such heterotrimers, although there is evidence for peptide-free dimers which may by conformationally unstable. One particularly intriguing aspect of MHC-restricted antigen recognition is the fact that cells from a given individual express only about a half dozen different class I MHC molecules which collectively must present a potentially vast number of possible peptide antigens, implying a certain amount of degeneracy in peptide-MHC protein binding.

Descriptors :   *T LYMPHOCYTES, *GLYCOPROTEINS, *ANTIGENS, VIRUSES, PEPTIDES.

Subject Categories : Medicine and Medical Research
      Biochemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE