NK and CD8+ T cell-mediated eradication of poorly immunogenic B16-F10 melanoma by the combined action of IL-12 gene therapy and 4-1BB costimulation

Int J Cancer. 2004 Apr 20;109(4):499-506. doi: 10.1002/ijc.11696.


In previous reports, systemic administration of a stimulatory monoclonal antibody directed against the 4-1BB receptor had no effect on survival or tumor burden in mice inoculated with the poorly immunogenic B16-F10 melanoma. We combined IL-12 gene transfer with 4-1BB costimulation to explore a previously noted cooperative anti-tumor effect against this model tumor. We hypothesize that the innate immune response mediated by IL-12-activated natural killer (NK) cells initiates the activation of the immune system, leading to the priming of T cells, whereas 4-1BB costimulation enhances the function of primed tumor-specific T cells. The effect of the combination therapy on the growth of subcutaneous (s.c.) tumors and pulmonary metastasis was examined. The combination therapy significantly retarded the growth of subcutaneously-inoculated tumors, and 50% of tumor-bearing mice survived with complete tumor regression. In contrast, neither IL-12 gene transfer nor anti-4-1BB antibody administration alone was as effective. Enhanced CTL activity against both B16-F10 tumor cells and TRP-2-pulsed EL4 syngeneic tumor cells was observed in tumor-bearing animals treated with the combination therapy 2 weeks after treatment and, in long-term survivors from this combination therapy, at >120 days. In a pulmonary metastatic model, only the combination therapy generated significant protection against metastasis. In vivo depletion of NK or CD8(+) but not CD4(+) subsets eliminated the protective immunity. Furthermore, NK cell depletion significantly reduced both tumor-specific CTL activity and the number of tumor-specific IFN-gamma-producing cells, suggesting that this synergistic effect requires the participation of both NK and CD8(+) T cells.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adenoviridae / genetics
  • Animals
  • Antibodies, Monoclonal / therapeutic use
  • Antigens, CD
  • CD8-Positive T-Lymphocytes / immunology*
  • Combined Modality Therapy
  • Drug Synergism
  • Female
  • Genetic Therapy*
  • Genetic Vectors / administration & dosage
  • Genetic Vectors / genetics
  • Immunity, Cellular
  • Immunotherapy
  • Interleukin-12 / administration & dosage*
  • Killer Cells, Natural / immunology*
  • Lung Neoplasms / immunology
  • Lung Neoplasms / secondary
  • Lung Neoplasms / therapy
  • Lymphocyte Depletion
  • Melanoma, Experimental / immunology*
  • Melanoma, Experimental / pathology
  • Melanoma, Experimental / therapy
  • Mice
  • Mice, Inbred C57BL
  • Receptors, Nerve Growth Factor / immunology*
  • Receptors, Tumor Necrosis Factor / immunology*
  • Skin Neoplasms / immunology
  • Skin Neoplasms / therapy
  • T-Lymphocytes, Cytotoxic
  • Tumor Necrosis Factor Receptor Superfamily, Member 9


  • Antibodies, Monoclonal
  • Antigens, CD
  • Receptors, Nerve Growth Factor
  • Receptors, Tumor Necrosis Factor
  • Tnfrsf9 protein, mouse
  • Tumor Necrosis Factor Receptor Superfamily, Member 9
  • Interleukin-12