Mimicking homeostatic proliferation in vitro generates T cells with high anti-tumor function in non-lymphopenic hosts

Cancer Immunol Immunother. 2013 Mar;62(3):503-15. doi: 10.1007/s00262-012-1350-1. Epub 2012 Sep 23.

Abstract

CD8(+) T cells undergoing homeostatic proliferation (HP) in a lymphopenic environment acquire a central memory-like phenotype (CD44(+) CD62L(+) Ly6c(+)). Such cells are readily functional in vitro, with a strong capacity to secrete IFNγ and IL-2 and to lyse target cells upon antigen recognition. In vivo, these memory-like T cells display potent anti-tumor reactivity. When addressing whether these remarkable properties were "acquired" or dependent on sustained HP, we observed, for the first time, that memory-like T cells retained full anti-tumor functions even when removed from their lymphopenic environment and retransferred into non-lymphopenic P14/Rag2(-/-) recipients (where HP is prevented). Moreover, memory-like T cells were superior to in vitro expanded effector T cells. We next sought to determine the conditions required to reproduce such a potent phenotype in vitro, in order to obtain optimal cells for adoptive cell transfer therapy. Assessing ex vivo lymph node cultures, dendritic cells, fibroblastic reticular cells, and HP-associated cytokines, we found that stimulation of naïve T cells with anti-CD3/CD28 beads and IL-15 (IL-7 was dispensable) led to the generation of memory-like T cell with a similar phenotype. Both in vitro and in vivo memory-like T cells retained the capacity to efficiently control tumor growth in non-lymphopenic hosts upon adoptive cell transfer. A similar phenotype could be imparted to human peripheral blood leukocytes with comparable culture conditions. Our data reinforce the idea that in vitro-generated memory-like T cells could benefit adoptive cell transfer therapies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CD28 Antigens / immunology
  • CD3 Complex / immunology
  • CD8-Positive T-Lymphocytes / immunology*
  • Cell Line, Tumor
  • Dendritic Cells / immunology
  • Homeostasis / immunology
  • Humans
  • Immunologic Memory / immunology*
  • Immunotherapy, Adoptive / methods*
  • Lymphocyte Activation / immunology
  • Lymphopenia / immunology
  • Mice
  • Mice, 129 Strain
  • Mice, Inbred C57BL
  • Neoplasms / immunology*
  • Neoplasms / therapy*
  • T-Lymphocyte Subsets / immunology

Substances

  • CD28 Antigens
  • CD3 Complex