Bioreactor Development for Cartilage Tissue Engineering: Computational Modelling and Experimental Results

Tissue engineering is an emerging technology to replace tissues and organs damaged due to trauma of disease with fully functional living tissue equivalents. Tissue development is facilitated by bioreactors, devices engineered to deliver appropriate spatial and temporal nutrient transport and mechanical loading in a welldefined and controlled environment. Bioreactors that provide well-defined and controllable environments are useful for fundamental studies to optimize tissue growth and as production units for large-scale tissue production bioprocesses. We have developed a concentric cylinder bioreactor and a perfusion concentric cylinder bioreactor suitable for growth of relatively thin (~1-3 mm thick) tissues under well-defined and controllable bioprocessing conditions. Using cartilage as a model tissue, we identify the role of mechanical loading, tissue perfusion and growth factors on tissue development. Since hydrodynamic profiles and nutrient gradients are complex during tissue growth, we demonstrate the utility of computational fluid dynamics (CFD) modelling of bioreactor growth conditions on bioreactor design, bioreactor scale-up and tissue growth.