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Updated: Aug 16, 2026

A High Throughput MHC II Binding Assay for Quantitative Analysis of Peptide Epitopes
Published on: March 25, 2014
Intramembrane proteolysis of signal peptides: an essential step in the generation of HLA-E epitopes
M K Lemberg1, F A Bland, A Weihofen
1Institute of Biochemistry, Swiss Federal Institute of Technology (Eidgenössiche Technische Hochschule), Zurich, Switzerland.
Abstract:
Signal sequences of human MHC class I molecules are a unique source of epitopes for newly synthesized nonclassical HLA-E molecules. Binding of such conserved peptides to HLA-E induces its cell surface expression and protects cells from NK cell attack. After cleavage from the pre-protein, we show that the liberated MHC class I signal peptide is further processed by signal peptide peptidase in the hydrophobic, membrane-spanning region. This cut is essential for the release of the HLA-E epitope-containing fragment from the lipid bilayer and its subsequent transport into the lumen of the endoplasmic reticulum via the TAP.
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