Principles of Bioreactor Design for Tissue Engineering

Tissue-engineering bioreactors apply engineering concepts to mimic native tissue environment and function, and study cellular responses under biologically sound conditions. A bioreactor must support 3D tissue development, maintain cell viability and function within a tissue, and provide appropriate molecular and physical cues. To date, the bioreactor designs have increasingly progressed to the point that allows us to generate fully viable and functional tissue grafts, study complex biological responses under normal and pathological conditions, improve tissue culture methods, and conduct drug screening under conditions predictable of human situation. Current advances in bioreactor designs and operation for tissue engineering largely focus on (i) generation of complex human tissue grafts for clinical application, (ii) studies of sophisticated biological responses that will open up novel directions for tissue regeneration, and (iii) optimization of high-throughput tissue culture techniques for fundamental research of stem cells and study of disease. We discuss here the principles of bioreactor design – in particular with respect to mass transport and physical signaling, and describe some examples of advanced bioreactor designs to illustrate how the biologically inspired bioreactor design is being implemented in tissue engineering, study of stem cells, and high-throughput screening.