Study on the in vivo Degradation and in vitro Biocompatibility of Spider Silk Protein Composite Material Small Diameter Vascular Scaffold
1 College of Life Sciences, Fujian Normal University, Fuzhou 350108, China
2 College of Life Sciences and Technology, Xinxiang Medical University, Xinxiang 453003, Henan, China;Key Laboratory of Biomedical Materials，Xinxiang Medical University, Xinxiang 453003, Henan, China
Abstract：The in vivo degradation performance and in vitro biocompatibility of small diameter vascular scaffold made of spider silk protein composite material was evaluated for clinical application. RGDrecombinant spider silk protein (pNSR16), polycaprolactone (PCL), chitosan (CS) and gelatin (Gt) were blended to prepare spider silk protein composite material (pNSR16/PCL/CS)/(pNSR16/PCL/Gt) that was used for the fabrication of small diameter vascular scaffold using electrospinning technique. The scaffold was implanted into the muscle tissue of SD rat leg. The degradation property in vivo was evaluated by HE staining. The effect of scaffold extract on the mesenchymal stem cell colony formation, mitotic index, trypan blue dye exclusion rate, cytotoxicity and cell cycle were analyzed to evaluate the biocompatibility of the scaffold. During the implantation period the scaffold degraded continually, showing obvious fiber broken. The weight loss rate was 20.3% after 12 weeks of implantation, and the degradation rate was significantly higher than that of (PCL/CS)/(PCL/Gt) scaffold that degraded 13.2% after 12 weeks of implantation. When cultivated with of the extract of (pNSR16/PCL/CS)/(pNSR16/PCL/Gt) scaffold, the colony formation rate, average colony area and mitotic index of rat bone marrow MSC were significantly higher than that with the extract of (PCL/CS)/(PCL/Gt) scaffold. The toxicity level of scaffold was less than level 1. The trypan blue dye exclusion rate for MSCs was greater than 95% in the extract of the composite scaffold,. After 48 h incubation with the extract, G0/1 phase ratio of cells was reduced, S and G2/M phase ratio was increased. The in vivo degradation and in vitro biocompatibility of scaffold made of spider silk protein composite material were acceptable, showing certain feasibility in clinical application.
