Abstract
Gene-activated matrix has wide potential utilization in tissue engineering. It may genetically
modify cells with plasmid DNA encoding therapeutic genes and allow sustained expression and release of
the proteins to surrounding tissues. In this study, we assessed the feasibility of the local gene release from
human fibronectin (HFN) substrate and the efficacy of local release of stromal cell-derived factor-1 (SDF-1)
gene on c-kit+ cell homing. Cationic polymer polyethylenimine (25kDa PEI) was used as non-viral DNA vector.
Gene-activated HFN (GAH) was prepared by mixing PEI/DNA complexes with HFN substrate. The DNA
retardation, the complex size, and the DNA release speed from the GAH were studied. The in vitro transfection
was optimized by luciferase expression and cell viability assay in the COS7 cell line. Localized gene expression
in COS7 cells cultured on the GAH was assessed by LacZ and GFP-N3-SDF-1 marker genes. Ckit+
cell homing was investigated in response to the local in vitro SDF-1 expression from rat mesenchymal
stem cells (RMSCs) cultured on GAH. Results showed GAH allows long time-sustained DNA release, localized
gene delivery, and high transfection efficiency. Local SDF-1 expression with GAH is a promising method
to induce targetable stem cell homing.
