A TLR9 agonist enhances therapeutic effects of telomerase genetic vaccine

Vaccine. 2010 Apr 30;28(20):3522-30. doi: 10.1016/j.vaccine.2010.03.020. Epub 2010 Mar 21.


The telomerase reverse transcriptase (TERT) is an attractive target for cancer vaccination because its expression is reactivated in most tumors. In this study, we have evaluated the ability of a genetic vaccine targeting murine TERT (mTERT) based on DNA electroporation (DNA-EP) and adenovirus serotype 6 (Ad6) to exert therapeutic effects in combination with a novel TLR9 agonist, referred to as immune modulatory oligonucleotide (IMO), as an adjuvant. IMO was administered to mice at the same time as vaccine. IMO induced dose-dependent cytokine secretion and activation of NK cells. Most importantly, vaccination of mice with IMO in combination with mTERT vaccine conferred therapeutic benefit in tumor bearing animals and this effect was associated with increased NK, DC and T cell tumor infiltration. These data show that appropriate combination of a DNA-EP/Ad6-based cancer vaccine against TERT with IMO induces multiple effects on innate and adaptive immune responses resulting in a significant antitumor efficacy.

MeSH terms

  • Adaptive Immunity
  • Adenoviridae
  • Adjuvants, Immunologic / genetics
  • Animals
  • Cancer Vaccines / genetics
  • Cancer Vaccines / immunology*
  • Cytokines / immunology
  • Cytokines / metabolism
  • Dendritic Cells / immunology
  • Electroporation
  • Female
  • Immunity, Innate
  • Killer Cells, Natural / immunology
  • Melanoma, Experimental / immunology
  • Melanoma, Experimental / prevention & control
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • Oligonucleotides / immunology
  • T-Lymphocytes / immunology
  • Telomerase / immunology*
  • Toll-Like Receptor 9 / agonists*
  • Vaccines, DNA / genetics
  • Vaccines, DNA / immunology*
  • Xenograft Model Antitumor Assays


  • Adjuvants, Immunologic
  • Cancer Vaccines
  • Cytokines
  • Oligonucleotides
  • Toll-Like Receptor 9
  • Vaccines, DNA
  • Telomerase
  • Tert protein, mouse