Page 114 - Tailoring Electrospinning Techniques for Regenerative Medicine - Marc Simonet

CHAPTER 5
for example, by producing core-shell fibers or embedding the biomolecules in hollow or porous microspheres. This protects the biomolecules during the electrospinning process against the solvent and allows for triggered release by external or internal factors.68 Another promising option is to directly incorporate the biomolecules into the side chains or the backbone of the polymer.57 As soon as relevant biomolecules are identified for heart valve tissue engineering, these can be incorporated into the heart valve sca old using one of the described techniques.
5.7 Future trends
Most of the tissue requirements defined for heart valve tissue engineering can be obtained with electrospinning methods. Combining the various electrospinning methods and techniques is challenging, since they are not always compatible. For example, the addition of bioactive factors o en reduces the electrospinning possibilities and results in less sca old design freedom. Nevertheless, to obtain a functional heart valve, these methods need to be integrated into one complex three- dimensional heart valve sca old, containing the three-layered structure. Each of these layers should ideally include tailored bioactivity and mechanical properties. E orts are undertaken in identifying
the best combination and concentration of the various bioactive factors and the implementation into the electrospun structure at the dedicated locations. In particular for the in-situ heart valve tissue engineering approach fatigue and creep of the sca old structures should be studied in more detail. To deal with patient to patient variations in neo- tissue formation, degradation should be controlled externally or triggered directly by the amount of cells and produced ECM. Further, built-in contrast agents allow for monitoring of sca old degradation and function of the heart valve in the patient a er implantation. Only a multidisciplinary approach will finally result in a functional three-dimensional valve sca old, which will inspire the cellular microenvironment, guide cell growth, di erentiation and functional tissue organization towards the ideal heart valve replacement that allows for growth and remodeling.
5.8 Acknowledgment
This research forms part of the Project P1.01 iValve of the research program of the BioMedical Materials institute, co-funded by the Dutch Ministry of Economic A airs. The financial contribution of the Nederlandse Hartstichting is gratefully acknowledged.
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