Transfer of in vitro-expanded naïve T cells after lymphodepletion enhances antitumor immunity through the induction of polyclonal antitumor effector T cells

PLoS One. 2017 Aug 30;12(8):e0183976. doi: 10.1371/journal.pone.0183976. eCollection 2017.

Abstract

The adoptive transfer of effector T cells combined with lymphodepletion has demonstrated promising antitumor effects in mice and humans, although the availability of tumor-specific T cells is limited. We and others have also demonstrated that the transfer of polyclonal naïve T cells induces tumor-specific effector T cells and enhances antitumor immunity after lymphodepletion. Because tumors have been demonstrated to induce immunosuppressive networks and regulate the function of T cells, obtaining a sufficient number of fully functional naïve T cells that are able to differentiate into tumor-specific effector T cells remains difficult. To establish culture methods to obtain a large number of polyclonal T cells that are capable of differentiating into tumor-specific effector T cells, naïve T cells were activated with anti-CD3 mAbs in vitro. These cells were stimulated with IL-2 and IL-7 for the CD8 subset or with IL-7 and IL-23 for the CD4 subset. Transfer of these hyperexpanded T cells after lymphodepletion showed significant antitumor efficacy, and tumor-specific effector T cells were primed from these expanded T cells in tumor-bearing hosts. Moreover, these ex vivo-expanded T cells maintained T cell receptor diversity and showed long-term persistence of memory against specific tumors. Further analyses revealed that combination therapy consisting of vaccination with dendritic cells that were co-cultured with irradiated whole tumor cells and the transfer of ex vivo-expanded T cells significantly enhanced antitumor immunity. These results indicate that the transfer of ex vivo-expanded polyclonal T cells can be combined with other immunotherapies and augment antitumor effects.

MeSH terms

  • Adoptive Transfer / methods*
  • Animals
  • CD4-Positive T-Lymphocytes / cytology
  • CD4-Positive T-Lymphocytes / immunology*
  • CD4-Positive T-Lymphocytes / transplantation*
  • CD8-Positive T-Lymphocytes / cytology
  • CD8-Positive T-Lymphocytes / immunology
  • Cell Culture Techniques
  • Cell Line, Tumor
  • Cell Proliferation
  • Cells, Cultured
  • Dendritic Cells / immunology
  • Dendritic Cells / transplantation
  • Female
  • Interleukin-2 / immunology
  • Interleukin-23 / immunology
  • Interleukin-7 / immunology
  • Lymphocyte Activation
  • Lymphocyte Depletion
  • Mice, Inbred C57BL
  • Neoplasms / immunology
  • Neoplasms / therapy*
  • Receptors, Antigen, T-Cell / immunology

Substances

  • Interleukin-2
  • Interleukin-23
  • Interleukin-7
  • Receptors, Antigen, T-Cell

Grants and funding

This work was supproted by Japan Society for the Promotion of Science KAKENHI Grant Number JP15K09168 to SW. http://www.jsps.go.jp/english/index.html. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.