Tissue Engineering: Complete Autologous Valve Conduit -
A New Moulding Technique^∗

Objective: The use of fibrin gel, which can be produced from patients’ blood, was investigated as an autologous, biodegradable scaffold. A new moulding technique was developed to create a complete aortic root. Methods: A new moulding technique was generated for the creation of complete valve conduit. On the basis of biomechanical valve design studies, a tricuspid ‘ventricular’ and ‘aortic’ stamp were developed. A silicone-coated aluminum cylinder was used to circumferentially limit the mould. The cell/gel suspension was filled into the mould and polymerization was started. Results: The creation of complex structures such as complete valve conduits is possible with the moulding technique described. With a layer thickness of up to 2 mm, histological investigations showed excellent tissue development with viable fibroblasts surrounded by collagen bundles. Conclusion: Fibrin gel unifies many properties of an ideal scaffold: The formation of complex structures is possible, the degradation and polymerization is controllable and the formation of the extracellular matrix is excellent.

Tissue engineering - Heart valves - Fibrin gel - Molding technique

Reference

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1 Presented at the 14^th Annual Meeting of the German Society for Thoracic and Cardiovascular Surgery; Leipzig, Germany, 21^th February 2001; Ethicon Award 2001