IDENTIFICATION OF AN IMMUNOGENIC EWS-FLI1-DERIVED HLA-DR-RESTRICTED T HELPER CELL EPITOPE

Abstract

Immunotherapy with tumor-specific peptide-loaded dendritic cells represents a promising therapeutic approach for patients with multifocal primary or early relapsed Ewing family tumors (EFT). The authors therefore screened a peptide library derived from the fusion region of the EFT-specific chimeric transcription factor EWS-FLI1 for immunogenic peptides. T-cell priming with 10 peptides was evaluated using IFN_γ video-assisted automated enzyme-linked immunospot technique. The authors report the identification of the first EFT-specific immunogenic T-cell epitope so far. Its identification will lead to a better understanding of EFT immunology and may improve DC-based immunotherapy.

Keywords:

• dendritic cells
• Ewing family tumors
• peptide epitope
• tumor vaccination