A major barrier in the development of a clinically-useful small-diameter tissue engineered vascular graft (TEVG) is the scaffold component. Scaffold requirements include matching the mechanical and structural properties with those of native vessels and optimizing the microenvironment to foster cell integration, adhesion, and growth. We have developed a small-diameter, bi-layered, biodegradable, elastomeric scaffold based on a synthetic, biodegradable elastomer. The scaffold incorporates a highly porous inner layer, allowing cell integration and growth, and an external, fibrous reinforcing layer deposited by electrospinning. Scaffold morphology and mechanical properties were assessed, quantified, and compared to those of native vessels. Scaffolds were then seeded with adult stem cells via a rotational vacuum seeding device to obtain a TEVG, cultured in dynamic conditions for 7 days, and evaluated for cellularity. The scaffold showed a firm integration of the two polymeric layers with no delaminations. Mechanical properties were physiologically-consistent showing anisotropy, elastic modulus (1.4±0.4 MPa), and ultimate tensile stress (8.3±1.7 MPa) comparable with native vessels. Compliance and suture retention force were 4.6±0.5×10−4 mmHg−1 and 3.4±0.3 N, respectively. Seeding resulted in a rapid, uniform, bulk integration of cells, with a seeding efficiency of 92±1%. The scaffolds maintained a high level of cellular density throughout dynamic culture. This approach, combining artery-like mechanical properties and a rapid and efficient cellularization, might contribute to the future clinical translation of TEVGs.
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