Papers by Author: Frédéric Couet

Abstract: Functional vascular tissue engineering aims to produce blood vessels in vitro in a controlled environment named bioreactor. In order to control the growth and remodeling of vascular tissues, suitable measurements should be made on the construct in situ, i.e. during the growth. These measurements will feed the controller with information in order to take efficient control decisions. The non-destructive measurement of compliance or elastic modulus in vitro is a potential indicator of the vascular construct maturity. This work shows that compliance and elastic modulus are related: they can be estimated during the growth of constructs in a bioreactor, and thus provide useful feedback information to the controller.

Abstract: One of the merging methods to produce tissue-engineered vascular substitutes is to process scaffolds to direct the regeneration of vascular tissues. Collagen, as one of the main protein in the vascular extracellular matrix, is one of biopolymers that exhibits a major potential for scaffold technology. However, gels made from reconstituted collagen generally exhibit poor mechanical properties and limited manipulability. Therefore, adding a reinforcement to the scaffold to make the structure resist to the physiological constraints applied during the regeneration represents a valid alternative. Silk fibroin is an interesting reinforcing candidate being a mechanically strong natural fibre, susceptible to proteolytic degradation in vivo and showing acceptable biological performances. Therefore, the aim of this study was to develop a model of a composite scaffold obtained by controlling the filament geometry winding of silk fibroin in the collagen gel. A finite element model taking into account the orthotropic elasticity of arteries has been combined with classic laminate theory applied to the filament winding of a tubular vessel. The design of the small structure susceptible to scaffold the vascular tissue regeneration was optimised by mean of an evolutive algorithm with the imperative to mimic the experimentally measured mechanical properties (compliance) of a native artery.