Development of a fibrous poly (xylitol sebacate) sheet for endothelial basement membrane tissue engineering.

An essential part of designing cardiovascular grafts is the fabrication of an artificial endothelial basement membrane (EBM) with the ability to support endothelial differentiation, especially under physiological dynamic forces. In this study, we introduce a novel artificial EBM constructed from a poly (xylitol sebacate) (PXS) polymer. First, the PXS prepolymer (pPXS) was blended with polyvinyl alcohol (PVA) at different ratios to achieve optimized production with a minimum amount of PVA to fabricate well-organized electrospun fiber networks of pPXS/PVA. Subsequently, pPXS/PVA was cross-linked at 120 °C under vacuum for two days to form a cPXS/PVA meshwork. Then, PVA and remaining pPXS were removed from the cPXS/PVA meshworks by serial rinsing in deionized water and ethanol to fabricate a defect-free fibrous sheet of cPXS. The fibrous cPXS sheets were characterized in terms of their structural, mechanical, and biological performance. The results confirmed that the cPXS sheets exhibited appropriate mechanical strength, acceptable wettability, ideal porosity, degradation behavior, and superior biocompatibility. Moreover, cPXS, as an artificial EBM, is capable of supporting endothelial differentiation of mesenchymal stem cells under dynamic culture conditions in a parallel plate bioreactor. Therefore, it can be inferred that fibrous cPXS sheet can be an ideal candidate for EBM tissue engineering and development of functional cardiovascular grafts.