Media tissue regeneration of the hybrid expanded polytetrafluoroethylene vascular graft via gelatin coating

We engineered a vascular media tissue by employing a hybrid ePTFE graft scaffold and vascular smooth muscle cells. The hybrid ePTFE scaffolds consisted of two porous biodegradable poly(lactide-co-glycolide) thin layers on the inner and the outer surfaces of the non-biodegradable ePTFE layer. The porous structure of the PLGA layers was obtained for control of tissue regeneration by gas-forming of ammonium bicarbonates as porogens. To improve tissue regeneration, we coated with gelatin on the porous biodegradable PLGA surface after testing its cellular adhesion over other biopolymers such as chitosan, fibrin and collagen. Media tissue regeneration was successfully achieved on the PLGA layer and their result was dependent on employment of gelatin coating and tissue culture period. While the two PLGA layers were expected to serve as biological layers of intima, media and adventitia of the blood vessel after their transformation into engineered tissues, the ePTFE in the middle of the hybrid scaffold did as a mechanically supporting layer.