Modulation of neo-endothelialization of vascular graft materials by silk fibroin

Controlled neo-endothelialization is critical to the patency of vascular grafts. Expanded polyethylene terephthalate (PET) vascular grafts were grafted with polyethylene glycol (PEG), irradiated with ultraviolet light, and subsequently coated with silk fibroin (SF) and EDC in a dip-coating process. Endothelial cells were cultivated on the coated samples for 1, 3, 5, and 7 days, and characterized by fluorescence microscopy and scanning electron microscopy (SEM). The quantitative analyse of CCK-8 method was used to assess ECs proliferation. The results reveal the correlation between grafting components and cell adhesion. We demonstrated that PET with SF grafting facilitated cell adhesion and spreading. Following 7 days of cell culture in vitro, PET-PEG6000-SF (PEG molecular weight 6,000) displayed spreading of cells over a significantly larger area. Rapid endothelialization on a modified PET surface resulted in large tissue pack that can be observed by SEM.