Immunization with Epstein-Barr Virus (EBV) peptide-pulsed dendritic cells induces functional CD8+ T-cell immunity and may lead to tumor regression in patients with EBV-positive nasopharyngeal carcinoma

Abstract

Nasopharyngeal Carcinoma (Npc), A Common Neoplasm In Southeast Asia, Is Ebv-Positive And Expresses A Limited Number Of Antigens, Including Latent Membrane Protein 2. In This Study, Autologous Monocyte-Derived Dendritic Cells Were Cultured From Patients With Advanced Npc, Matured With Cytokine, Pulsed With Hla-A1101-, A2402-, Or B40011-Restricted Epitope Peptides From Ebv Latent Membrane Protein 2 And Injected Into Inguinal Lymph Nodes. Sixteen Patients With Local Recurrence Or Distant Metastasis After Conventional Therapies Received Four Injections At Weekly Intervals. Epitope-Specific Cd8+ T-Cell Responses Were Elicited Or Boosted In 9 Patients Receiving Hla-A1101- Or A2402-Restricted Peptides, With Stronger Responses Seen To The A1101 Peptide. Furthermore, Epitope-Specific Cytotoxicity Was Detectable In Peripheral Blood T Cells Harvested At 3-Months After Vaccination From A1101-Responsive Patients, And In 2 Patients, This Coincided With Partial Tumor Reduction. Approaches Leading To Stronger And More Sustained Ebv-Specific T-Cell Responses, Therefore, May Have Therapeutic Potential In The Context Of Npc.