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Updated: Jun 1, 2026
08:09
Peptide Scanning-assisted Identification of a Monoclonal Antibody-recognized Linear B-cell Epitope
Published on: March 24, 2017
An antigenic peptide produced by reverse splicing and double asparagine deamidation
Alexandre Dalet1, Paul F Robbins, Vincent Stroobant
1Ludwig Institute for Cancer Research, Brussels Branch, Université Catholique de Louvain, B-1200 Brussels, Belgium.
Summary
This study reveals a unique melanoma antigen peptide derived from tyrosinase. It involves reverse splicing of fragments and post-translational modification of asparagine to aspartate, enhancing cancer immunity.
Area of Science:
- Immunology
- Molecular Biology
- Oncology
Background:
- Antigenic peptides presented by MHC class I molecules are crucial for immune surveillance.
- Unconventional mechanisms expand the repertoire of peptides presented to the immune system.
Purpose of the Study:
- To characterize a novel, post-translationally modified antigenic peptide recognized by tumor-infiltrating lymphocytes.
- To elucidate the biogenesis and presentation pathway of this unique peptide in melanoma.
Main Methods:
- Analysis of tumor-infiltrating lymphocytes from melanoma patients.
- Peptide sequencing and mass spectrometry to identify modifications.
- Cellular assays to confirm peptide processing and presentation.
Main Results:
- Identified a peptide derived from tyrosinase, featuring reverse splicing of noncontiguous fragments.
- Confirmed post-translational conversion of asparagine to aspartate via deamidation by peptide-N-glycanase.
- Demonstrated natural presentation of this modified peptide on melanoma cells.
Conclusions:
- This unconventional peptide processing pathway generates a diverse antigenic repertoire for MHC class I presentation.
- The identified peptide represents a potential target for melanoma immunotherapy.
- Understanding these mechanisms enhances knowledge of tumor antigen generation.
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