dr. Anita Mol

Background—In heart valve tissue engineering, the optimization of tissue properties has to be combined with the realization of a completely autologous tissue engineering approach to obtain a functional and living heart valve replacement. Autologous conditions already have been improved by using human cell sources. However, culture conditions and scaffolds still have to be optimized. This study is based on the successful use of the scaffold system of PGA/P4HB combined with bovine fibrin as a cell carrier. However, to create a fully autolo-gous approach the use of animal-derived fibrin has to be avoided and transferred to human fibrin. Methods and Results—Human fibrin characteristics which are important for tissue engi-neering applications such as gelation time and cell distribution, were optimized by varying thrombin and fibrinogen concentration in a fibrin disk model system. Thrombin concentration was shown to influence gelation time, and thrombin and fibrinogen concentration both influ-enced cell density and distribution. The optimized human fibrin gels were further tested by analyzing their suitability as a cell carrier in a well-known tissue engineering system. Human fibrin seeded constructs showed similar quantitative and qualitative tissue formation and me-chanical properties as bovine fibrin seeded constructs. Finally, human fibrin was successfully used as a cell carrier to tissue engineer a trileaflet heart valve. Conclusion—This study demonstrated the feasibility of human fibrin as a cell carrier in com-bination with a PGA/P4HB scaffold for heart valve tissue engineering, bringing a completely autologous tissue engineering approach one step closer to reality.