AGE-RELEATED CHANGES IN BIOMECHANICAL AND MORPHOLOGICAL PROPERTIES OF TRANSGENIC PORCINE VALVE DEDICATED FOR THE USE IN TISSUE ENGINEERING APPLICATIONS

Objectives: Because of the imbalance of the donor and recipient, the cardiac valves derived from pigs do not express the galactose 1, 3 galactose (-Gal) antigen, and are attractive source for the preparations of tissue engineered heart valve. Due to the differentiation of recipient there is a need for the preparations of different size valve prosthesis. The aim of the study was to estimate how the age and weight of the transgenic porcine can influence the morphological and blomechanical properties of the valve prosthesis and how the size of the bioprosthesis, dedicated for different recipient can be controlled. Methods: The morphological and biomechanical properties of acellular aortic and pulmonary valve in relations to the age and weight of transgenic porcine were tested. The valve morphology was analyzed using H&E and Masson staining. Uninaxial tensile test was used to estimate the biomechanical properties of the examinated valve. The computer simulations based on Finite Etements Methods (FEM) was used to study the influence of the decellularizations procedure on the hemodynamic conditions. Results: The differences in the morphology and biomechanical properties of the acellular pulmonary and aortic valve were observed. Uniaxial tensile test demonstrated that the Energy to Break, Peak Load or Peak Stress of the aortic valve increase in relation to weight and age. For the pulmonary valve, the value of these parameters was constant, they were independent of weight and age of the animals. The value of biomechanical parameters was significantly lower for the pulmonary valve compared with the aortic valve. Conclusions: The aortic valve derived from transgenic porcine is more valuable for the preparations of different size bioprosthesis. The use of tissue engineered pulmonary valve as an aortic valve replacement can be strongly limited.