REVIEWStem cell bioprocessing: fundamentalsand principlesMark R. Placzek, I-Ming Chung, Hugo M. Macedo, Siti Ismail,Teresa Mortera Blanco, Mayasari Lim, Jae Min Cha, Iliana Fauzi,Yunyi Kang, David C. L. Yeo, Chi Yip Joan Ma, Julia M. Polak,Nicki Panoskaltsis†and Athanasios Mantalaris*Biological Systems Engineering Laboratory, Centre for Process Systems Engineering,Department of Chemical Engineering, Imperial College London, South Kensington Campus,London SW7 2AZ, UKIn recent years, the potential of stem cell research for tissue engineering-based therapies andregenerative medicine clinical applications has become well established. In 2006, Chungpioneered the first entire organ transplant using adult stem cells and a scaffold for clinicalevaluation. With this a new milestone was achieved, with seven patients with myelomeningo-cele receiving stem cell-derived bladder transplants resulting in substantial improvements intheir quality of life. While a bladder is a relatively simple organ, the breakthrough highlightsthe incredible benefits that can be gained from the cross-disciplinary nature of tissueengineering and regenerative medicine (TERM) that encompasses stem cell research and stemcell bioprocessing. Unquestionably, the development of bioprocess technologies for the transferof the current laboratory-based practice of stem cell tissue culture to the clinic as therapeuticsnecessitates the application of engineering principles and practices to achieve control,reproducibility, automation, validation and safety of the process and the product. Thesuccessful translation will require contributions from fundamental research (from develop-mental biology to the ‘omics’ technologies and advances in immunology) and from existingindustrial practice (biologics), especially on automation, quality assurance and regulation. Thetimely development, integration and execution of various components will be critical—failuresof the past (such as in the commercialization of skin equivalents) on marketing, pricing,production and advertising should not be repeated. This review aims to address theprinciples required for successful stem cell bioprocessing so that they can be applied deftly toclinical applications.Keywords: stem cell; bioprocessing; tissue engineering1. INTRODUCTIONThe success of stem cell bioprocessing relies on robustand reproducible culture conditions and processes. Forstem cell bioprocessing, this includes the scale-up ofstem cells to a differentiated end product of sufficientquality and quantity for clinical and commercial goals.The considerable cost with respect to consumables,labour and time as well as the inherent variability inmanual processes not only make this an unattractiveoptionbutalsorenderitcommerciallyunviable.