An Anisotropically and Heterogeneously Aligned Patterned Electrospun Scaffold with Tailored Mechanical Property and Improved Bioactivity for Vascular Tissue Engineering

The development of vascular scaffolds with controlled mechanical 'properties and stimulatory effects on biological,activities of endothelial, cells still remains a, significant challenge to vascular tissue engineering. In this work, we reported an innovative approach to prepare a new type of vascular scaffolds with anisotropically and heterogeneously aligned patterns using electrospitining technique with uniquewire spring templates, and further investigated the Structural effects of the patterned electrospun scaffolds on mechanical' properties and angiogenic differentiation of hhman umbilical vein endothelial cells (HUVECs). Results showed that anisotropically aligned patterned,nanofibrous structure was obtained by depositing nanofibers on template in a structurally different manner, one part of nariofibers,densely deposited on the embossments Of nfrire Spring and formed cylindrical-like structures in the translierse direction, while others tobsely suspended and aligned along the longitudinal direction) forming a three-dimensional porous Microstructure. We further found that such structures could efficiently control the mechanical properties of electrospuri vascular scaffolds in both longitudinal and transverse directions by altering the interval distances between- the embossments of patterned scaffolds. When HUVECs were chltured an scaffolds with different microstructure, the patterned scaffolds distinctively promoted adhesion of HUVECs at early stage and proliferation during the culture periods Most importantly, cells experienced a large shape Change associated with tell oskeleton and nuclei remodeling leading to a stimulatory effect on angiog enesis differentiation, of HUVECS by the patterned' microstructures of electrospum scaffolds, and the scaffolds with larger distances of intervals showed a higher stimulatory effect. These results siiggest that electrospun scaffold's with the athsotropically and heterogeneously aligned patterns, which could efficiently control the mechanical properties and bioactivities of the scaffolds, might have great potential in vascular tissue engineering application.