AccScience Publishing / IJB / Volume 10 / Issue 1 / DOI: 10.36922/ijb.1111

Successful endothelial monolayer formation on melt electrowritten scaffolds under dynamic conditions to mimic tunica intima

Sebastian Loewner1 Sebastian Heene1 Fabian Cholewa2 Henrik Heymann2 Holger Blume2 Cornelia Blume1*
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1 Institute of Technical Chemistry, Leibniz University Hannover, Hannover, Lower Saxony, Germany
2 Institute of Microelectronic Systems, Leibniz University Hannover, Hannover, Lower Saxony, Germany
IJB 2024, 10(1), 1111
Submitted: 20 June 2023 | Accepted: 14 August 2023 | Published: 11 September 2023
© 2023 by the Author(s). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( )

The lack of transplantable tissues and organs as well as the limitations of synthetic implants highlight the need for tissue-engineered constructs to obtain safe, long-lasting, and limitless tissue replacements. Scaffolds for cardiovascular applications, such as for a tissue-engineered vascular graft (TEVG), are thus highly required. For TEVGs, tubular scaffolds should support the formation of confluent endothelial layers in particular under dynamic conditions to prevent thrombosis and maintain hemostasis. For that purpose, a porous and highly diffusible scaffold structure is necessary to allow optimal cell adhesion as well as oxygen and nutrient exchange with the surrounding tissue. Here, we present a three-dimensional-printed scaffold made by a combination of fused deposition modeling (FDM) and melt electrowriting (MEW) out of polycaprolactone that enables monolayer formation and alignment of endothelial cells in the direction of medium flow under a shear stress of up to 10 dyn cm-2. Pore size and coating with human fibrin were optimized to enable confluent endothelial layers on the printed scaffold structures. Cell orientation and shape analysis showed a characteristic alignment and elongation of the tested endothelial cells with the direction of flow after dynamic cultivation. In contrast, melt electrospun scaffolds based on the same CAD design under comparable printing and cultivation conditions were not sufficient to form gapless cell layers. Thus, the new scaffold fabricated by MEW/FDM approach appears most suitable for TEVGs as a template for the innermost vascular wall layer, the tunica intima.

Tissue engineering
Melt electrowriting
Dynamic cultivation
This work was carried out within the framework of the SMART BIOTECS alliance between the Technische Universitaet Braunschweig and the Leibniz University Hannover. This initiative is supported by the Ministry of Economy and Culture (MWK) of Lower Saxony, Germany.
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Conflict of interest
The authors declare no conflicts of interest.
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International Journal of Bioprinting, Electronic ISSN: 2424-8002 Print ISSN: 2424-7723, Published by AccScience Publishing