GeneJammer® Enhances Cellular Transduction with Recombinant Adenovirus

DILLING, C. M.; BOSCH, P.; DAVIS, A. R.; SHAFER, J. A.; STICE, S. L.; BIKRAM, M.; OLMEST-DAVIS, E. A.

St. Louis, MO, USA

Congreso; American Society of Gene Therapy 2005 Annual Meeting; 2005

American Society of Gene Therapy

Viral vectors are extensively used to deliver exogenous DNA in eukaryotic cells for a broad range of applications from basic research to potential clinical uses.  Adenoviruses are particularly attractive vectors due to their ability to infect a wide range of cell types.  A limiting step in recombinant adenovirus uptake in certain cell types is the internalization into the target cells which is mediated by membrane receptors.  Although polyamines have been widely studied regarding their ability to enhance transfer of DNA into cells, little is known about their potential role in viral transduction of cells. In this study, we have investigated the ability of polyamines present in GeneJammer® transfection reagent (Stratagene, La Jolla, CA) to enhance in vitro adenoviral transduction efficiency of cell types lacking adenoviral receptors.  When GeneJammer® was present during transduction of human bone marrow mesenchymal stem cells (hBM-MSC) with an adenovirus type 5 carrying the eGFP gene (Ad5eGFP), infection efficiency was enhanced (82%) compared with that in the control without the polyamine p<0.001).  FACS analysis demonstrated that the enhancement was due to an increased number of cells expressing the transgene, however when we obtained 98% transduction of the cells, we did observe a shift in intensity of GFP expression suggesting that we were able to internalize more viral particles per cell.  We also demonstrated a 14% enhancement in transduction efficiency when human peripheral blood mononuclear cells were transduced by a chimeric Ad5 vector that contains an adenovirus type 35 fiber (Ad5F35eGFP) in the presence of GeneJammer®. Finally, we confirmed that transduction enhancement induced by GeneJammer® was not specific to adenoviruses carrying the marker gene GFP, by performing both in vitro and in vivo studies using Ad5 and Ad5F35 vectors containing the gene for human bone morphogenetic protein 2 (BMP2).  BMP2 activity in the supernatant of transduced cells was determined by a biological assay.  Supernatants of hBM-MSC transduced with Ad5BMP2 in the presence of GeneJammer® elicited a 30 fold increase in alkaline phosphatase activity of W20/17 cells compared with that in controls transduced without GeneJammer, reflecting an increase in BMP2 production.  Using the same assay, we detected a 36% increase in BMP2 activity in peripheral blood mononuclear cells exposed to GeneJammer® during transduction with Ad5F35BMP2. Furthermore, mineralized bone was radiologically identified in mice receiving cells transduced with Ad5BMP2 in the presence of Genejammer® while little to undetectable amount of bone was present in mice that received cells transduced in absence of the polyamine. We conclude that the polyamine used in this study, GeneJammer® transfection reagent can markedly increase the efficiency of adenovirus-mediated gene transfer and suggests a new role for this type of molecules in this process.