**A Novel Biodegradable Multilayered Bioengineered Vascular Construct with a Curved Structure and Multi-Branches**

**Yuanyuan Liu 1, Yi Zhang 1, Weijian Jiang 2, Yan Peng 1,\*, Jun Luo 1, Shaorong Xie 1, Songyi Zhong 1, Huayan Pu 1, Na Liu 1 and Tao Yue 1,\***


Received: 15 March 2019; Accepted: 21 April 2019; Published: 24 April 2019

**Abstract:** Constructing tissue engineered vascular grafts (TEVG) is of grea<sup>t</sup> significance for cardiovascular research. However, most of the fabrication techniques are unable to construct TEVG with a bifurcated and curved structure. This paper presents multilayered biodegradable TEVGs with a curved structure and multi-branches. The technique combined 3D printed molds and casting hydrogel and sacrificial material to create vessel-mimicking constructs with customizable structural parameters. Compared with other fabrication methods, the proposed technique can create more native-like 3D geometries. The diameter and wall thickness of the fabricated constructs can be independently controlled, providing a feasible approach for TEVG construction. Enzymatically-crosslinked gelatin was used as the material of the constructs. The mechanical properties and thermostability of the constructs were evaluated. Fluid-structure interaction simulations were conducted to examine the displacement of the construct's wall when blood flows through it. Human umbilical vein endothelial cells (HUVECs) were seeded on the inner channel of the constructs and cultured for 72 h. The cell morphology was assessed. The results showed that the proposed technique had good application potentials, and will hopefully provide a novel technological approach for constructing integrated vasculature for tissue engineering.

**Keywords:** bioengineered vascular constructs; curved structure; multi-branches; enzymaticallycrosslinked; tissue engineering
