Ex vivo interleukin-12-priming during CD8(+) T cell activation dramatically improves adoptive T cell transfer antitumor efficacy in a lymphodepleted host

J Am Coll Surg. 2012 Apr;214(4):700-7; discussion 707-8. doi: 10.1016/j.jamcollsurg.2011.12.034. Epub 2012 Feb 22.


Background: Clinical application of adoptive T cell therapy has been hindered by an inability to generate adequate numbers of nontolerized, functionally active, tumor-specific T cells, which can persist in vivo. In order to address this, we evaluated the impact of interleukin (IL)-12 signaling during tumor-specific CD8(+) T cell priming in terms of persistence and antitumor efficacy using an established B16 melanoma tumor adoptive therapy model.

Study design: B6 mice were injected subcutaneously with B16 melanoma tumor cells. On day 12 of tumor growth, mice were preconditioned with cyclophosphamide (4mg dose, intraperitoneally), and 1 day later were treated by adoptive transfer of tumor-specific pmel-1 CD8(+) T cells primed ex vivo 3 days earlier with both IL-12 and antigen (hGP100(25-33) peptide) or antigen only. Tumors were measured biweekly, and infused donor T cells were analyzed for persistence, localization to the tumor, phenotype, and effector function.

Results: Adoptive transfer of tumor-specific CD8(+) T cells primed with IL-12 was significantly more effective in reducing tumor burden in mice preconditioned with cyclophosphamide compared with transfer of T cells primed without IL-12. This enhanced antitumor response was associated with increased frequencies of infused T cells in the periphery and tumor as well as elevated expression of effector molecules including granzyme B and interferon-γ (IFNγ).

Conclusions: Our findings demonstrate that ex vivo priming of tumor-specific CD8(+) T cells with IL-12 dramatically improves their in vivo persistence and therapeutic ability on transfer to tumor-bearing mice. These findings can be directly applied as novel clinical trial strategies.

Publication types

  • Evaluation Study
  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • CD8-Positive T-Lymphocytes / immunology
  • CD8-Positive T-Lymphocytes / transplantation*
  • Cell Line, Tumor
  • Cyclophosphamide / administration & dosage
  • Female
  • Flow Cytometry
  • Immunosuppressive Agents / administration & dosage
  • Immunotherapy, Adoptive / methods*
  • Interleukin-12 / immunology*
  • Lymphocyte Activation*
  • Male
  • Melanoma / immunology
  • Melanoma / pathology
  • Melanoma / therapy*
  • Mice
  • Mice, Inbred C57BL
  • Treatment Outcome
  • Tumor Burden


  • Immunosuppressive Agents
  • Interleukin-12
  • Cyclophosphamide