Tumor-reprogrammed resident T cells resist radiation to control tumors

Nat Commun. 2019 Sep 2;10(1):3959. doi: 10.1038/s41467-019-11906-2.

Abstract

Successful combinations of radiotherapy and immunotherapy depend on the presence of live T cells within the tumor; however, radiotherapy is believed to damage T cells. Here, based on longitudinal in vivo imaging and functional analysis, we report that a large proportion of T cells survive clinically relevant doses of radiation and show increased motility, and higher production of interferon gamma, compared with T cells from unirradiated tumors. Irradiated intratumoral T cells can mediate tumor control without newly-infiltrating T cells. Transcriptomic analysis suggests T cell reprogramming in the tumor microenvironment and similarities with tissue-resident memory T cells, which are more radio-resistant than circulating/lymphoid tissue T cells. TGFβ is a key upstream regulator of T cell reprogramming and contributes to intratumoral Tcell radio-resistance. These findings have implications for the design of radio-immunotherapy trials in that local irradiation is not inherently immunosuppressive, and irradiation of multiple tumors might optimize systemic effects of radiotherapy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Cell Movement / genetics
  • Cell Survival / genetics
  • Combined Modality Therapy
  • Gene Expression Profiling / methods
  • Immunotherapy / methods*
  • Interferon-gamma / immunology
  • Interferon-gamma / metabolism
  • Lymphocytes, Tumor-Infiltrating / immunology
  • Lymphocytes, Tumor-Infiltrating / metabolism*
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Mice, Transgenic
  • Neoplasms, Experimental / genetics
  • Neoplasms, Experimental / immunology
  • Neoplasms, Experimental / therapy*
  • Radiation Tolerance / genetics
  • Radiotherapy / methods*

Substances

  • Interferon-gamma