Controllable fiber orientation and nonlinear elasticity of electrospun nanofibrous small diameter tubular scaffolds for vascular tissue engineering.

Biomimetic structures play an important role in controlling the cell behaviors of adhesion, proliferation, migration, and differentiation, which is beneficial for the regeneration of defective tissues. Scaffolds with a biomimetic structure are highly desirable in tissue engineering. In this study, we successfully fabricated three different types of tubular scaffold with randomly, circumferentially, and axially aligned structures, using synthetic bioabsorbable poly(L-lactide-co-caprolactone) via electrospinning. Pre-extension treatment of the tubular scaffolds provided nonlinear elasticity that mimicked the nonlinear elasticity of arteries in the human body, which protects these blood vessels from damage. We measured the nonlinear elasticity, fatigue properties, compliance, and burst pressure of the tubular scaffolds, and the results indicated that the properties of the scaffolds matched those of native vessels reported in the literature. Furthermore, human umbilical vein endothelial cells were cultured on random and aligned fibers, and the results revealed that the cells proliferated well on nanofibrous mats with the three different fiber orientation directions, and the aligned fibers facilitated the orientation of cells in the direction of alignment of the fibers. Therefore, the aligned tubular scaffolds might have potential in vascular tissue engineering.