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RESEARCH ARTICLE

Coaxial Electrohydrodynamic Bioprinting of

Pre-vascularized Cell-laden Constructs for Tissue

Engineering

Mao Mao , Hongtao Liang , Jiankang He *, Ayiguli Kasimu , Yanning Zhang , Ling Wang ,
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Xiao Li , Dichen Li 1,2
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1 State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
2 NMPA Key Laboratory for Research and Evaluation of Additive Manufacturing Medical Devices, Xi’an Jiaotong
University, Xi’an 710049, China
Abstract: Recapitulating the vascular networks that maintain the delivery of nutrition, oxygen, and byproducts for the living
cells within the three-dimensional (3D) tissue constructs is a challenging issue in the tissue-engineering area. Here, a novel
coaxial electrohydrodynamic (EHD) bioprinting strategy is presented to fabricate thick pre-vascularized cell-laden constructs.
The alginate and collagen/calcium chloride solution were utilized as the outer-layer and inner-layer bioink, respectively, in
the coaxial printing nozzle to produce the core-sheath hydrogel filaments. The effect of process parameters (the feeding rate
of alginate and collagen and the moving speed of the printing stage) on the size of core and sheath lines within the printed
filaments was investigated. The core-sheath filaments were printed in the predefined pattern to fabricate lattice hydrogel
with perfusable lumen structures. Endothelialized lumen structures were fabricated by culturing the core-sheath filaments
with endothelial cells laden in the core collagen hydrogel. Multilayer core-sheath filaments were successfully printed into
3D porous hydrogel constructs with a thickness of more than 3 mm. Finally, 3D pre-vascularized cardiac constructs were
successfully generated, indicating the efficacy of our strategy to engineer living tissues with complex vascular structures.
Keywords: Electrohydrodynamic bioprinting; Coaxial bioprinting; Vascularized tissues; Biofabrication; Core-sheath filaments

*Correspondence to: Jiankang He, State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049,
China; jiankanghe@mail.xjtu.edu.cn

Received: April 3, 2021; Accepted: May 14, 2021; Published Online: June 4, 2021
(This article belongs to the Special Section: Bioprinting of 3D Functional Tissue Constructs)
Citation: Mao M, Liang H, He J, et al., 2021, Coaxial Electrohydrodynamic Bioprinting of Pre-vascularized Cell-laden
Constructs for Tissue Engineering. Int J Bioprint, 7(3):362. http://doi.org/10.18063/ijb.v7i3.362

1. Introduction endothelial cells in the spatially predefined organization,
with an attempt to build microvessels within the cell-
One of the most challenging problems in the tissue laden constructs [4-8] . It has been demonstrated that the
engineering area is to fabricate functional vasculature endothelial cells in the spatially predefined organization
within the three-dimensional (3D) engineered tissue can significantly improve the speed and extent of the
that provides enough nutrition and oxygen to the cells vascularization after implantation, compared to that in
and transports the byproducts . Cellular viability a random distribution [9,10] . However, these engineering
[1]
and function will be compromised, and necrosis may methods could only be used to fabricate constructs with
further occur without a capillary network within a few relatively simple architectures and homogeneous cell-
hundred microns of cells [2,3] . Thus, many approaches laden matrices, which make them difficult to recapitulate
such as microreplication, photolithography, and the intricate 3D structure and composition of natural
sacrificial molding have been proposed to organize the tissues [11,12] .

© 2021 Mao, et al. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/
licenses/by/4.0/), permitting distribution and reproduction in any medium, provided the original work is cited.
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