Particle-mediated gene transfer of granulocyte-macrophage colony-stimulating factor cDNA to tumor cells: implications for a clinically relevant tumor vaccine.
The necessity for prolonged tissue culture manipulations limits the clinical application of many form of gene therapy in patients with malignancies. We hypothesized that granulocyte-macrophage colony-stimulating factor (GM-CSF) cDNA in a plasmid expression vector could be effectively introduced into resting tumor cells, without the need for tissue culture propagation prior to or following transfection, and that efficient expression of transgenic GM-CSF by the transfected tumor cells would confer an effective immune response against tumors. GM-CSF cDNA in expression vectors was coated onto gold particles and accelerated with a gene gun device into mouse and human tumor cells. Human tumor tissue transfected within 4 hr of surgery produced significant levels of transgenic human GM-CSF protein in vitro. Human GM-CSF was readily detectable in serum and at the injection site following subcutaneous implantation of these transfected tumor cells into nude mice. Transfected and irradiated murine B16 melanoma cells produced > or = 100 ng/ml murine GM-CSF/10(6) cells per 24 hr in vitro for at least 10 days. The antitumor efficacy of this nonviral approach was tested using irradiated B16 tumor cells that were transfected with mGM-CSF cDNA and injected into mice as tumor "vaccine". Subsequent challenge of these mice with nonirradiated, nontransfected B16 tumor cells showed that 58% of the animals wer protected from the tumor by the prior vaccine treatment. In contrast, only 2% of control animals were protected by prior treatment with irradiated B16 cells transfected with the vector containing the luciferase gene. These results suggest that particle-mediated transfection of fresh tumor explants with cytokine cDNA is an effective and clinically attractive approach for cancer therapy.
Mahvi
D M
DM
Department of Surgery, University of Wisconsin, Madison 53792, USA.
Burkholder
J K
JK
Turner
J
J
Culp
J
J
Malter
J S
JS
Sondel
P M
PM
Yang
N S
NS
D000818:Animals; D019470:Biolistics; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism*; D005720:Gamma Rays; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D018014:Gene Transfer Techniques; D005822:Genetic Vectors / Q000235:genetics; D006046:Gold / Q000378:metabolism; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000235:genetics*; D006653:Histology; D006801:Humans; D007167:Immunotherapy; D051379:Mice; D008815:Mice, Inbred Strains; D009369:Neoplasms / Q000628:therapy; D009374:Neoplasms, Experimental / Q000378:metabolism; D010316:Particle Size; D014162:Transfection / Q000235:genetics; D014407:Tumor Cells, Cultured; D014612:Vaccines / Q000276:immunology*
D018076:DNA, Complementary; D014612:Vaccines; D006046:Gold; D016178:Granulocyte-Macrophage Colony-Stimulating Factor