Graphene Oxide Incorporated PLGA Nanofibrous Scaffold for Solid Phase Gene Delivery into Mesenchymal Stem Cells

Delivery of functional genes into stem cells shows great application prospect in DNA-based tissue engineering. However, comparing with epithelial cells and cancer cells, stem cells usually exhibit low gene transfection efficiency. To enhance the transfection efficiency, non-viral gene delivery in combination with biomaterial scaffolds, has raised increasing interests from researchers in tissue engineering. Nanofibers fabricated by electrospinning technique mimicking extracellular matrix (ECM) are widely used in tissue engineering applications. In addition, graphene oxide (GO) with ultrahigh specific surface area and ultra-strong adsorption capability, is an ideal candidate for gene delivery. In this work, polyethylenimine (PEI)/plasmid DNA-GO/ poly(D,L-lactic-co-glycolic acid) (PLGA) scaffold was developed as a substrate for solid phase gene delivery and a tissue engineering substrate for stem cells growth and differentiation. In order to improve the transfection efficiency of stem cells, PEI/pDNA complexes were immobilized at the surface of electropun GO incorporated PLGA nanofibrous mat. Human embryonic kidney 293 cells and human umbilical cord derived mesenchymal stem cells cultured on PEI/pDNA-GO/PLGA scaffold showed significantly higher green fluorescent protein (GFP) expression than PEI/pGFP in the medium. These findings demonstrated that solid phase gene delivery using PEI/pDNA-GO/PLGA significantly enhanced the gene transfection efficiency, and may find potential application of gene therapy and regeneration medicine.