TiO₂Nanotubes Micro-Groove Influence Of Directional Differentiation Of MSCs

Currently, the implanted medical devices for the treatment of cardiovascular diseases would cause intimal injury at different level, which thereby induces restenosis. Therefore, the study of promoting endothelialization of the implanted biomaterials has attracted more and more attention. In recent years, with the in-depth research of differentiation of the induced stem cells,it was found that the multi-function submersible cells (MSC) could be induced to differentiate into vascular cells. Thus using the tissue engineering principles and methods to explore the differentiation of MSC into vascular cells has a certain significance.In this study, the methods of light etching technique and two anodic oxidation were used to prepare the micro-grooves titania nanotubes (NANO-TOPO),which were used as the experimental samples. Meanwhile, the titania nanotubes (NANO-GRO) samples fabricated via light etching technique and one anodic oxidation, titania nanotubes (NANO) samples via the simple anode oxidation, and the flat Ti without any surface modification were used as control sample in order to study the regulation of stem cells (MSC). The morphologies of the samples were imaged by SEM. The surface chemical composition was examined by FTIR. The crystal structure of the TiO2was detected by XRD. The surface wettability was measured by a method of water contact angle. The results showed that the size of the prepared trench graphics was20/10μm, the size of the nanotube was about70nm and the crystal structure was anatase phase. According to the results that the prepared sample composite experimental content requirements.(rewrite the sentence) MSC obtained from less than4-week-old SD rats was used as the seed cells in order to ensure the purity of the cells. The identification of the stem cell phenotype of the extraction of MSC was performed using CD44factor.Short-term cell experiments showed that the topology micro-grooves titania nanotubes (NANO-TOPO) not only influenced the regulation of cell growth orientation, but also allowed the morphogenesis polarization of MSC, and the trend did not disappear when the multilayer growth of cells on the surface of the material occured, which may be related to the size of the nanotube diameter and the morphology of groove structure. The experimental results of long-term induction showed that the topologied micro-grooves titania nanotubes (NANO-TOPO) could not only regulate the MSC growth orientation, but also effectively controlled the direction of their differentiation. The identification of the cells sequentially excluded the possibility of inducing synaptic cells, osteoblasts, endothelial cells. Eventually, the cell-specific marker alpha-SMA and CNN-1of smooth muscle cells were expressed6-week culture, which primarily suggested that the topologied micro-grooves titania nanotubes (NANO-TOPO) had the ability to induce the differentiation of MSC into smooth muscle-like cells. Smooth muscle cells as a natural part of the organic composition of the blood vessels played an important supporting role on vascular endothelial cells, therefore, the present study provides an effective carrier for the bionic construction of vascular endothelial function, and paid the way for the next study.