Journal of Clinical and Cellular Immunology
Open Access

ERAP1-ERAP2 dimers trim MHC I-bound precursor peptides: Understanding peptide editing

8^th European Immunology Conference

June 29-July 01, 2017 Madrid, Spain

Marlene Bouvier, Lenong Li, Hanna Chen, Mirjana Weimershaus, Irini Evnouchidou and Peter van Endert

University of Illinois at Chicago, USA
INSERM, France
Universite Paris Descartes, France

Posters & Accepted Abstracts: J Clin Cell Immunol

Abstract :

Statement of the Problem: The human endoplasmic reticulum amino peptidase 1 (ERAP1) and ERAP2 are critically important in the final processing of MHC class I antigens in the endoplasmic reticulum. To date, the molecular context of peptide trimming by ERAPs and how ERAPs shape antigen repertoires remains open questions. Methodology: Using a cell-free system composed of ERAP1 and ERAP2 heterodimers (ERAP1/2), MHC class I molecules and N-terminally extended model and natural peptides, we characterized the function of ERAP1/2. Findings: We provide evidence that ERAP1/2 trims MHC I-bound precursor peptides to the final lengths, albeit more slowly than the corresponding free precursors. We show that trimming of MHC I-bound precursors by ERAP1/2 increases the conformational stability of MHC I/peptide complexes. Conclusion & Significance: Our study provides new findings on ERAP1/2 as a key antigen processing complex. From our data, we propose a molecular mechanistic model of ERAP1/2 as an editor of class I antigens. Understanding class I antigen processing is significant given the role that class I antigens play in the normal recognition of virally infected and transformed cells by CD8+ T cells.

Biography :

Email: mbouvier@uic.edu