Targeting CD4(+) T-helper cells improves the induction of antitumor responses in dendritic cell-based vaccination

Cancer Res. 2013 Jan 1;73(1):19-29. doi: 10.1158/0008-5472.CAN-12-1127. Epub 2012 Oct 18.

Abstract

To evaluate the relevance of directing antigen-specific CD4(+) T helper cells as part of effective anticancer immunotherapy, we investigated the immunologic and clinical responses to vaccination with dendritic cells (DC) pulsed with either MHC class I (MHC-I)-restricted epitopes alone or both MHC class I and II (MHC-I/II)-restricted epitopes. We enrolled 33 stage III and IV HLA-A*02:01-positive patients with melanoma in this study, of whom 29 were evaluable for immunologic response. Patients received intranodal vaccinations with cytokine-matured DCs loaded with keyhole limpet hemocyanin and MHC-I alone or MHC-I/II-restricted tumor-associated antigens (TAA) of tyrosinase and gp100, depending on their HLA-DR4 status. In 4 of 15 patients vaccinated with MHC-I/II-loaded DCs and 1 of 14 patients vaccinated with MHC-I-loaded DCs, we detected TAA-specific CD8(+) T cells with maintained IFN-γ production in skin test infiltrating lymphocyte (SKIL) cultures and circulating TAA-specific CD8(+) T cells. If TAA-specific CD4(+) T-cell responses were detected in SKIL cultures, it coincided with TAA-specific CD8(+) T-cell responses. In 3 of 13 patients tested, we detected TAA-specific CD4(+)CD25(+)FoxP3(-) T cells with high proliferative capacity and IFN-γ production, indicating that these were not regulatory T cells. Vaccination with MHC-I/II-loaded DCs resulted in improved clinical outcome compared with matched control patients treated with dacarbazine (DTIC), median overall survival of 15.0 versus 8.3 months (P = 0.089), and median progression-free survival of 5.0 versus 2.8 months (P = 0.0089). In conclusion, coactivating TAA-specific CD4(+) T-helper cells with DCs pulsed with both MHC class I and II-restricted epitopes augments TAA-specific CD8(+) T-cell responses, contributing to improved clinical responses.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Antigens, Neoplasm / immunology
  • CD8-Positive T-Lymphocytes / immunology
  • Cancer Vaccines / immunology*
  • Dendritic Cells / immunology*
  • Dendritic Cells / transplantation*
  • Disease-Free Survival
  • Epitopes, T-Lymphocyte / immunology
  • Female
  • Flow Cytometry
  • Histocompatibility Antigens Class I / immunology
  • Histocompatibility Antigens Class II / immunology
  • Humans
  • Kaplan-Meier Estimate
  • Lymphocyte Activation / immunology
  • Male
  • Melanoma / immunology*
  • Melanoma / therapy*
  • Middle Aged
  • Neoplasm Staging
  • T-Lymphocytes, Helper-Inducer / immunology*
  • Young Adult

Substances

  • Antigens, Neoplasm
  • Cancer Vaccines
  • Epitopes, T-Lymphocyte
  • Histocompatibility Antigens Class I
  • Histocompatibility Antigens Class II