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

Abstract

Constructing tissue engineered vascular grafts (TEVG) is of great 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.

The status and challenges of replicating the mechanical properties of connective tissues using additive manufacturing

“…The compressive moduli of bioprinted gelatin methacryloyl/poly(ethylene glycol)-tetra-acrylate (PEGTA) scaffolds at 10% strain ranged from 24.2-50.7 kPa (Jia et al, 2016). Gelatin/microbial transglutaminase (mTG), of interest due to its ECM-like nature, was printed into the geometry of the left coronary artery using SLA and compressed to 60% strain, yielding a compressive modulus of 5 MPa (Liu et al, 2019a).…”

A modular microfluidic system based on a multilayered configuration to generate large-scale perfusable microvascular networks

“…There are several approaches to generate in vitro large and small vascular networks, including microfluidic device-based methods, such as microfabrication and manipulation [4][5][6][7] , hybrid methods, such as EC lining of microfluidic channels [8][9][10][11] , scaffold-based methods [12][13][14][15] , and biology-driven methods, such as de novo flowinduced vascular formation inside microfluidic devices [16][17][18][19][20] . Previously, our perfused microvascular networks were developed by engineering anastomoses between microvascular capillary networks and microfluidic channels 16 .…”

Editorial for the Special Issue on 3D Printing for Tissue Engineering and Regenerative Medicine

“…These constraints include: 1) limited number of available bioink solutions and lack of thorough characterization of their biological and physiomechanical properties [10,17]; 2) poor understanding of the correlation between printed architecture and the ultimate tissue function [18,19]; 3) limitations on the quality of imaging techniques [20,21] and available bioprinters [22]; 4) complex and rather expensive processes involved pre, during, and post-bioprinting [22]; 5) suboptimal, non-specialized printing software and their often incompatibilities [23].There are eight articles published in this Special Issue composed of four research papers and four review papers. The research articles focus on the influence of electron beam (E-beam) sterilization on in vivo degradation of composite filaments [24], enhancing osteogenic differentiation of stem cells using 3D printed wavy scaffolds [25], the development of a scaffold-free bioprinter [26], and the fabrication of multilayered vascular constructs with a curved structure and multi-branches [27]. Kang et al investigated the effect of E-beam sterilization on the degradation of β-tricalcium phosphate/polycaprolactone (β-TCP/PCL) composite filaments in a rat subcutaneous model for 24 weeks [24].…”

“…There are eight articles published in this Special Issue composed of four research papers and four review papers. The research articles focus on the influence of electron beam (E-beam) sterilization on in vivo degradation of composite filaments [24], enhancing osteogenic differentiation of stem cells using 3D printed wavy scaffolds [25], the development of a scaffold-free bioprinter [26], and the fabrication of multilayered vascular constructs with a curved structure and multi-branches [27]. Kang et al investigated the effect of E-beam sterilization on the degradation of β-tricalcium phosphate/polycaprolactone (β-TCP/PCL) composite filaments in a rat subcutaneous model for 24 weeks [24].…”

“…This scaffold-free bioprinter could potentially advance the growing field of scaffold-free 3D bioprinting. Liu et al developed a combined approached to fabricate multilayered biodegradable vascular constructs for cardiovascular research [27]. In their approach, 3D printing was used to fabricate a mold system which was then used to cast a hydrogel and a sacrificial material.…”