In vitro re-endothelialization of detergent decellularized heart valves under simulated physiological dynamic conditions

Abstract

The production of viable biological heart valves is of central interest in tissue engineering (TE). The aim of this study was to generate decellularized heart valves with an intact ultra-structure and to repopulate these with endothelial cells (EC) under simulated physiological conditions. Decellularization of ovine pulmonary valve conduits was performed under agitation in detergents followed by six wash cycles. Viability of EC cultures exposed to washing solution served to prove efficiency of washing. Resulting scaffolds were free of cells with preserved extracellular matrix. Biomechanical standard tension tests demonstrated comparable parameters to native tissue. Luminal surfaces of decellularized valvular grafts were seeded with ovine jugular vein EC in dynamic bioreactors. After rolling culture for 48 h, pulsatile medium circulation with a flow of 0.1 L/min was started. The flow was incremented 0.3 L/min/day up to 2.0 L/min (cycle rate: 60 beats/min), while pH, pO2, pCO2, lactate and glucose were maintained at constant physiological levels. After 7 days, a monolayer of cells covered the inner valve surface, which expressed vWF, indicating an endothelial origin. A complete endothelialization of detergent decellularized scaffold can be achieved under simulated physiological circulation conditions using a dynamic bioreactor system, which allows continuous control of the culture environment.

Mouse stem cells seeded into decellularized rat kidney scaffolds endothelialize and remodel basement membranes

“…We believe it unlikely that there could be practical engineering methods that would mechanically place so many different types in a spatially appropriate architecture. Instead we have proposed that an appropriately prepared matrix 13,14 will retain the signals to trigger site-specific differentiation of pluripotent precursor cells, and thereby launch a cascade of matrix-cell, cell-cell 15 and cell-matrix events culminating in cycles of organ differentiation and remodeling of the original scaffold. The concept of matrix-induced cellular differentiation is not new, [16][17][18][19][20][21] and extends back to pioneering work by MJ Bissell.…”

Nanopatterned acellular valve conduits drive the commitment of blood-derived multipotent cells

“…58 As already reported in preclinical studies, 19 AVs have been shown to sustain the process of endothelization by stimulating the production of VEGFA and collagen 3 and 4. 59 The acquisition of VEC-like phenotype 43 was further demonstrated in both leaflets by the expression of von Willebrand factor protein.…”

Non-Invasive analysis of synthetic and decellularized scaffolds for heart valve tissue engineering

“…The promising approaches are the seeding of decellularized porcine or human heart valves and the application of synthetic materials such as polyurethane as scaffold materials. [11][12][13] Seeding is most frequently achieved using vascular or stem cells 14,15 Seeding scaffolds with autologous cells has the advantage of thrombogenicity and immunogenicity when implanted. 16 Decellularization success and seeding efficiency must be visualized in an attempt to develop quality control in tissue engineering.…”