(170f) A Porous Perfusion Bioreactor That Possess Microchannels: Its Fabrication by Selective Laser Sintering and Preliminary Evaluation of Culture of Human Hepatoma Hep G2 Cells

Objective: Towards the final goal to engineering an implantable liver tissue equivalent, we designed and fabricated a porous scaffold that possesses a branching and joining flow channel network using a selective laser sintering (SLS) 3D fabrication technique, and evaluated its efficiency in perfusion culture of human hepatoma Hep G2 cells. Materials and Methods: We designed 3D flow channel network (inner diameter is 1 mm) by accumulating unit tetrahedrons (edge length is 4 mm) for perfusion culture. The total volume of the scaffold was 10 cm³. Bioresorbable polycaprolactone (PCL) and 80% (w/w) of NaCl salt particles as a porogen were completely mixed and applied to the SLS process. The inner structure was evaluated by X ray CT. Hep G2 cells were seeded and cultured in the scaffolds with or without such flow channel network (as a control), and their growth and functions were compared. Results and discussions: After optimization of fabrication parameters, we successfully obtained a scaffold that had a high porosity of 89% with a mean pore size of 100-200 µm and a 3D network flow channels whose inner diameter is 800 µm. Results of X ray CT confirmed completely interconnected flow channels as designed. A preliminary perfusion culture over 9 days demonstrated that such microchannels was necessary to guide the cells to grow and function. The basic design concept herein shows great promise for engineering implantable liver tissue equivalents.