Development of endothelium-denuded human umbilical veins as living scaffolds for tissue-engineered small-calibre vascular grafts

Abstract

Tissue-engineered small-calibre vessel grafts may help to alleviate the lack of graft material for coronary and peripheral bypass grafting in an increasing number of patients. This study explored the use of endothelium-denuded human umbilical veins (HUVs) as scaffolds for vascular tissue engineering in a perfusion bioreactor. Vessel diameter (1.2 ± 0.4 mm), wall thickness (0.38 ± 0.09 mm), uniaxial ultimate failure stress (8029 ± 1714 kPa) and burst pressure (48.4 ± 20.2 kPa, range 28.4-83.9 kPa) were determined in native samples. The effects of endothelium removal from HUVs by enzymatic digestion, hypotonic lysis and dehydration were assessed. Dehydration did not significantly affect contractile function, tetrazolium dye reduction, mechanical strength and vessel structure, whereas the other methods failed in at least one of these parameters. Denudation by dehydration retained laminin, fibronectin, collagen and elastic fibres. Denuded HUVs were seeded in a perfusion bioreactor with either allogeneic HUVs endothelial cells or with saphenous vein endothelial cells harvested from patients with coronary artery disease. Seeding in a perfusion bioreactor resulted in a confluent monolayer of endothelial cells from both sources, as judged by histology and scanning electron microscopy. Seeded cells contained von Willebrand factor and CD31. In conclusion, denuded HUVs should be considered an alternative to decellularized blood vessels, as the process keeps the smooth muscle layer intact and functional, retains proteins relevant for biomechanic properties and for cell attachment and provides a suitable scaffold for seeding an autologous and flow-resistant endothelium.

Beyond Burst Pressure: Initial Evaluation of the Natural History of the Biaxial Mechanical Properties of Tissue-Engineered Vascular Grafts in the Venous Circulation Using a Murine Model

“…[18][19][20]22 Given the growing body of literature supporting the central importance of mechanobiological responses in vascular biology and the development of vascular disease, we have begun to characterize the evolving biomechanical properties of TEVGs in the hope of identifying roles of mechanobiological processes in neovessel formation, which is complex and dynamic. In native blood vessels, vascular cells respond to changes in the biomechanical environment by remodeling their ECM to promote mechanical homeostasis.…”

“…To date, biomechanical characterization of TEVGs has been largely limited to characterization of the burst pressure and suture retention strength of the TEVG scaffold. [18][19][20] These critical parameters must be evaluated to determine the clinical utility of any TEVG scaffold and we have previously measured these parameters for our scaffold. 6 Nevertheless, given our successful clinical experience using this TEVG in the Fontan circulation, which demonstrates the lack of aneurysmal dilation or rupture up to 10 years after implantation, it is time to take the next step and move beyond a basic mechanical characterization and into a more sophisticated analysis so that we can begin to understand better the complex, dynamic mechanobiological processes.…”

Evaluation of decellularized human umbilical vein (HUV) for vascular tissue engineering - comparison with endothelium-denuded HUV

“…In order to prepare endothelium‐denuded HUVs, endothelial cells were destroyed by dehydration, as described previously (Hoenicka et al ., ). In brief, the vessels were perfused with carbogen at 60 ml/min for 10 min and then rinsed thoroughly with culture medium.…”

“…We have previously investigated human umbilical veins (HUVs) as a source for TEBV and demonstrated that endothelium‐denuded HUVs can be seeded with autologous cells from CABG patients to form a confluent and flow‐resistant neoendothelium (Hoenicka et al ., , , ). The present study was undertaken to investigate the utility of decellularized HUV as scaffolds for vascular tissue engineering and to compare these two approaches.…”

Neue Verwendungsmöglichkeiten von Nachgeburtsgewebe für die Regenerative Medizin

“…Dies gelang durch Perfusion mit Carbogen (95 % Sauerstoff , 5 % Kohlendioxid). Weiterhin wurde ein Perfusionsbioreaktor benutzt, um durch Rotation während der Besiedelung die Gefäße auf dem gesamten Umfang mit Endothelzellen zu besiedeln und um die Strömungsresistenz des Neoendothels zu über-prüfen[ 44 ] . Schließlich konnte gezeigt werden, dass auch Endothelzellen aus der V. saphena von Patienten mit Koronarer Herzkrankheit auf diesem Scaff old ein strömungsresistentes Neoendothel ausbilden ( • ▶ Abb.…”