Cationic lipid gene transfer of an IL-2 transgene leads to activation of natural killer cells in a SCID mouse human tumor xenograft

Paul R. Clark, Alison T. Stopeck, Suezanne E. Parker, Evan M. Hersh

Research output: Contribution to journalArticle

5 Scopus citations


Natural killer (NK) cells play an important role in combating infectious and malignant diseases and interleukin-2 (IL-2) has been shown to promote proliferation and activation of NK cells in vitro and in vivo. Here we investigate the effects of local cationic lipid-mediated IL-2 gene transfer on intratumoral accumulation and activation of NK cells in a SCID mouse tumor model. UM449 human melanoma tumors in SCID mice received intratumoral injections of DMRIE/ DOPE admixed with VR1103, a DNA plasmid encoding the gene for human IL-2. Dissagregated tumor cells were tested for IL-2 secretion and were characterized using antibodies to asGM1, MAC-1, and F4/80 antigens. Granzyme A, a proteolytic serine esterase, was also measured in tumor cell lysates. IL-2 secretion from tumors injected with VR1103:DMRIE/DOPE peaked at 48 h after injection and fell to baseline levels on day 8. Intratumoral granzyme A activity was significantly increased in tumors injected with IL-2 plasmid:DMRIE/ DOPE complexes, but not by an irrelevant plasmid DNA:DMRIE/DOPE control. Importantly, the growth of UM449 tumors was slowed in VR1103:DMRIE/DOPE-injected tumors. These results indicate that local cationic lipid-mediated gene transfer of IL-2 induces activation of intratumoral NK cells and slows tumor growth. (C) 2000 Academic Press.

Original languageEnglish (US)
Pages (from-to)96-104
Number of pages9
JournalCellular Immunology
Issue number2
StatePublished - Sep 15 2000



  • Cationic lipid
  • Granzyme A
  • Interleukin-2
  • Intratumoral
  • Natural killer cell
  • Tumor

ASJC Scopus subject areas

  • Immunology

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