title: A Novel Bioreactor System for the Assessment of Endothelialization on Deformable Surfaces.
abstract: The generation of a living protective layer at the luminal surface of cardiovascular devices, composed of an autologous functional endothelium, represents the ideal solution to life-threatening, implant-related complications in cardiovascular patients. The initial evaluation of engineering strategies fostering endothelial cell adhesion and proliferation as well as the long-term tissue homeostasis requires in vitro testing in environmental model systems able to recapitulate the hemodynamic conditions experienced at the blood-to-device interface of implants as well as the substrate deformation. Here, we introduce the design and validation of a novel bioreactor system which enables the long-term conditioning of human endothelial cells interacting with artificial materials under dynamic combinations of flow-generated wall shear stress and wall deformation. The wall shear stress and wall deformation values obtained encompass both the physiological and supraphysiological range. They are determined through separate actuation systems which are controlled based on validated computational models. In addition, we demonstrate the good optical conductivity of the system permitting online monitoring of cell activities through live-cell imaging as well as standard biochemical post-processing. Altogether, the bioreactor system defines an unprecedented testing hub for potential strategies toward the endothelialization or re-endothelialization of target substrates.
authors.affiliation: ETH Zurich, Laboratory of Thermodynamics in Emerging Technologies, Sonneggstrasse 3, 8092 Zurich, Switzerland.
authors.forename: Björn J
authors.initials: BJ
authors.lastname: Bachmann
authors.affiliation: ETH Zurich, Institute for Mechanical Systems, Leonhardstrasse 21, 8092 Zurich, Switzerland.
authors.forename: Laura
authors.initials: L
authors.lastname: Bernardi
authors.affiliation: ETH Zurich, Laboratory of Composite Materials and Adaptive Structures, Department of Mechanical and Process Engineering, Tannenstrasse 3, CH-8092 Zurich, Switzerland.
authors.forename: Christian
authors.initials: C
authors.lastname: Loosli
authors.affiliation: ETH Zurich, Laboratory of Thermodynamics in Emerging Technologies, Sonneggstrasse 3, 8092 Zurich, Switzerland.
authors.forename: Julian
authors.initials: J
authors.lastname: Marschewski
authors.affiliation: ETH Zurich, Institute for Mechanical Systems, Leonhardstrasse 21, 8092 Zurich, Switzerland.|University Hospital Zurich, Department of Obstetrics, Zurich, Switzerland.
authors.forename: Michela
authors.initials: M
authors.lastname: Perrini
authors.affiliation: University Hospital Zurich, Department of Obstetrics, Zurich, Switzerland.
authors.forename: Martin
authors.initials: M
authors.lastname: Ehrbar
authors.affiliation: ETH Zurich, Laboratory of Composite Materials and Adaptive Structures, Department of Mechanical and Process Engineering, Tannenstrasse 3, CH-8092 Zurich, Switzerland.
authors.forename: Paolo
authors.initials: P
authors.lastname: Ermanni
authors.affiliation: ETH Zurich, Laboratory of Thermodynamics in Emerging Technologies, Sonneggstrasse 3, 8092 Zurich, Switzerland.
authors.forename: Dimos
authors.initials: D
authors.lastname: Poulikakos
authors.affiliation: ETH Zurich, Laboratory of Thermodynamics in Emerging Technologies, Sonneggstrasse 3, 8092 Zurich, Switzerland.
authors.forename: Aldo
authors.initials: A
authors.lastname: Ferrari
authors.affiliation: ETH Zurich, Institute for Mechanical Systems, Leonhardstrasse 21, 8092 Zurich, Switzerland.|Empa, Swiss Federal Laboratories for Materials Science &Technology, Überlandstr. 129, 8600 Dübendorf, Switzerland.
authors.forename: Edoardo
authors.initials: E
authors.lastname: Mazza
mesh_terms: D019149:Bioreactors; D003198:Computer Simulation; D042783:Endothelial Cells / Q000166:cytology*; D004867:Equipment Design; D006353:Heart-Assist Devices; D018056:Hemorheology; D006801:Humans; D007260:Infusion Pumps; D008954:Models, Biological; D011673:Pulsatile Flow; D033081:Shear Strength; D013314:Stress, Mechanical; D016474:Weight-Bearing