Abstract
Biomaterial scaffolds that serve as vehicles for gene delivery to promote expression of inductive factors have numerous regenerative medicine applications. In this report, we investigate plasmid delivery from biomaterial scaffolds using a surface immobilization strategy. Porous scaffolds were fabricated from poly(D,L-lactide-co-glycolide) (PLG), and plasmids were immobilized by drying. In vitro plasmid release indicated that the majority (70%) of adsorbed plasmids were released within 24 h and 98% within 3 days; however, in vivo implantation of the scaffolds at the subcutaneous site yielded transgene expression that persisted for at least 28 weeks and was localized to the site of implantation. Histological analysis of DNA-adsorbed scaffolds indicated that macrophages at the scaffold were transfected in the first 2 weeks after implantation, whereas muscle cells adjacent to the implant primarily expressed the transgene at 4 weeks. In addition to localized gene expression, a secreted protein (human factor IX) was retained at the implant site and not available systemically after 3 days, indicating minimal off-target effects. These findings show that surface immobilization of plasmid onto microporous PLG scaffolds can produce localized and long-term gene expression in vivo, which may be used to enhance the bioactivity of scaffolds used for regenerative medicine.
Original language | English (US) |
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Pages (from-to) | 1134-1141 |
Number of pages | 8 |
Journal | Gene therapy |
Volume | 17 |
Issue number | 9 |
DOIs | |
State | Published - Sep 2010 |
Funding
We thank Prof. Michele Calos for helpful discussions and the human Factor IX construct. Financial support for this research was provided by NIH RO1EB003806 and RO1EB005678.
ASJC Scopus subject areas
- Molecular Medicine
- Molecular Biology
- Genetics