Addition of interleukin-21 for expansion of T-cells for adoptive immunotherapy of murine melanoma

Int J Mol Sci. 2015 Apr 20;16(4):8744-60. doi: 10.3390/ijms16048744.

Abstract

We previously demonstrated that interleukin (IL)-7/15 was superior to IL-2 for expansion of T cells in vitro for adoptive immunotherapy. We sought to ascertain whether IL-21 would further improve yield and therapeutic efficacy of T cells in culture. Naïve T cell receptor (TcR) transgenic splenocytes or antigen-sensitized lymph node cells were harvested from PMEL-1 mice and exposed to bryostatin-1 and ionomycin (B/I) for 18 h. Cells were then cultured in IL-2, IL-21, IL-7/15 or IL-7/15/21 for six days. Harvested cells were analyzed by flow cytometry and used to treat C57Bl/6 mice injected intravenously with B16 melanoma. Lungs were harvested and metastases counted 14 days after treatment. Culturing lymphocytes in IL-7/15/21 increased expansion compared to IL-2 or IL-7/15. IL-21 and IL-7/15/21 increased CD8+ cells compared to IL-2 or IL-7/15. IL-21 preferentially expanded a CD8+CD44-CD62L+ T "naïve" population, whereas IL-7/15/21 increased CD8+CD44+CD62Lhigh central-memory T cells. T cells grown in IL-7/15/21 were more effective at reducing metastases than IL-2. The addition of IL-21 to IL-7/15 induced greater expansion of lymphocytes in culture and increased the yield of CD8+ T central-memory cells vs. IL-7/15 alone. This may have significant impact on future clinical trials of adoptive immunotherapy, particularly for generating adequate numbers of lymphocytes for treatment.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Proliferation
  • Cells, Cultured
  • Coculture Techniques
  • Cyclophosphamide / therapeutic use
  • Immunosuppressive Agents / therapeutic use
  • Immunotherapy, Adoptive
  • Interferon-gamma / metabolism
  • Interleukins / physiology*
  • Lung Neoplasms / secondary
  • Lung Neoplasms / therapy*
  • Melanoma, Experimental / pathology
  • Melanoma, Experimental / therapy*
  • Mice, Inbred C57BL
  • Neoplasm Transplantation
  • T-Lymphocytes / physiology*

Substances

  • Immunosuppressive Agents
  • Interleukins
  • Interferon-gamma
  • Cyclophosphamide
  • interleukin-21