Differentiation Induction of Mesenchymal Stem Cells by a Au Delivery Platform

Au decorated with type I collagen (Col) was used as a core material to cross-link with stromal cell-derived factor 1α (SDF1α) in order to investigate biological performance. The Au-based nanoparticles were subjected to physicochemical determination using scanning electron microscopy (SEM), dynamic light scattering (DLS) and ultraviolet–visible (UV-Vis) and Fourier-transform infrared spectroscopy (FTIR). Mesenchymal stem cells (MSCs) were used to evaluate the biocompatibility of this nanoparticle using the MTT assay and measuring reactive oxygen species (ROS) production. Also, the biological effects of the SDF-1α-conjugated nanoparticles (Au-Col-SDF1α) were assessed and the mechanisms were explored. Furthermore, we investigated the cell differentiation-inducing potential of these conjugated nanoparticles on MSCs toward endothelial cells, neurons, osteoblasts and adipocytes. We then ultimately explored the process of cell entry and transportation of the nanoparticles. Using a mouse animal model and retro-orbital sinus injection, we traced in vivo biodistribution to determine the biosafety of the Au-Col-SDF1α nanoparticles. In summary, our results indicate that Au-Col is a promising drug delivery system; it can be used to carry SDF1α to improve MSC therapeutic efficiency.