(485u) Insight Into Tissue Growth Process Via Local Shear Stress and Nutrient Transport Simulation in 3D Porous Scaffolds Cultured in a Perfusion Bioreactor

A wide variety of scaffold geometries are available for culturing osteoblastic cells in a flow perfusion bioreactor with the aim at bone tissue engineering applications, yet the question remains: what scaffold design is optimal for bone tissue growth? The answer depends on several factors, such as the flow regime under which the tissue is cultured, the amount of fluid shear forces experienced by the cells within the scaffold (mechanostimulation, detachment, bursting) and the efficiency of nutrient/waste transport to/away from the cells (osteoblast differentiation, proliferation, upregulation of angiogenic and osteogenic factors, and mineralized matrix production). Fundamental understanding of factors that lead to favorable cell differentiation can lead to scaffold design procedures that would maximize tissue growth. However, due to the inherently random architecture of the internal porous scaffolds structure, any theoretical prediction of tissue growth is impractical. Therefore, the focus of this work is to model local shear force and mass transport distributions within typical scaffolds (salt leeched and nonwoven fiber mesh PLLA) via computation. The modeling results are compared against high resolution Micro-Computed Tomography (μCT) scans of tissue growth as the tissue culturing experiment progresses with time. The juxtaposition of the local tissue growth and computer simulation results is used to obtain insight into the tissue growth process with the ultimate goal of being able to predict where the tissue will grow a priori ? based on the plain scaffold geometry, only. To the best of our knowledge this is the first study of its kind.