Enhanced transgene expression and effective in vivo antitumor immune responses initiated by dendritic progenitors transfected with a nonviral T7 vector expressing a model tumor antigen.
Genetic education of dendritic cells (DCs) with tumor-associated antigens is an encouraging development in DC-mediated tumor immunotherapy. In this study, to increase the transgene expression by DCs using nonviral vectors, a cytoplasmic T7 vector (T7T7/T7Luc) was used to transfect bone marrow-derived DCs with the firefly luciferase gene as a reporter and as a model tumor antigen. As a result, the luciferase activity of T7T7/T7Luc-transfected DCs was more than four times greater than that of DCs transfected with pCMVLuc, a commonly used nonviral vector. Furthermore, the luciferase activity was increased three times more when dendritic progenitor cells rather than mature DCs were transfected. In vivo tumor studies showed that T7T7/T7Luc-transfected DCs, which express high levels of luciferase (model tumor antigen), stimulated a stronger immune response than did pCMVLuc-transfected DCs, which express relatively low levels of luciferase, as indicated by the cytotoxic T lymphocyte assay. T7T7/T7Luc transfected DCs, when injected into recipient mice, evoked an antigen-specific immune response that can effectively eradicate implanted metastasis and prevent new tumor development by murine melanoma cells genetically modified to express luciferase. Therefore, the T7 system is a powerful nonviral vector that can be used to genetically educate DCs with tumor-associated antigens for tumor immunotherapy.
Wei
Y
Y
Oncology Research Institute, Greenville Hospital System Cancer Treatment Center, Greenville, South Carolina, USA.
Li
J
J
Chen
W Y
WY
Yu
X
X
Sticca
R P
RP
Wagner
T E
TE
D000818:Animals; D000951:Antigens, Neoplasm / Q000235:genetics* / Q000276:immunology; D001854:Bone Marrow Cells / Q000166:cytology; D002454:Cell Differentiation; D012321:DNA-Directed RNA Polymerases / Q000235:genetics; D003713:Dendritic Cells / Q000166:cytology / Q000378:metabolism*; D005260:Female; D015870:Gene Expression; D017930:Genes, Reporter; D005822:Genetic Vectors; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000378:metabolism*; D008156:Luciferases / Q000235:genetics; D051379:Mice; D008810:Mice, Inbred C57BL; D018448:Models, Immunological; D011401:Promoter Regions, Genetic; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D014162:Transfection; D019076:Transgenes; D014407:Tumor Cells, Cultured; D014764:Viral Proteins
D000951:Antigens, Neoplasm; D014764:Viral Proteins; D008156:Luciferases; C062210:bacteriophage T7 RNA polymerase; D012321:DNA-Directed RNA Polymerases