© 2011 THE AUTHORS 1046 BJU INTERNATIONAL © 2 0 11 B J U I N T E R N A T I O N A L | 1 0 8 , 1 0 4 6 – 1 0 6 5 | doi:10.1111/j.1464-410X.2011.10206.x BJUI BJU INTERNATIUONAL REVIEW ARTICLE Regenerative medicine in urology Felix Wezel* ‡ , Jennifer Southgate* and David F.M. Thomas † *Jack Birch Unit for Molecular Carcinogenesis, Department of Biology, University of York, York; † Paediatric Urology, St James’s University Hospital, Leeds, UK, and ‡ Department of Urology, University Medical Centre Mannheim, Germany What’s known on the subject? and What does the study add? Urology was one of the first specialties to report the introduction of regenerative medicine into clinical practice and has been at the forefront of scientific innovation. Despite the scale of investment and research effort, the promise of regenerative medicine remains largely unfulfilled. We review recent developments underpinning the emerging science of regenerative medicine and evaluate critically both the potential for novel regenerative therapies to transform urological practice and the outstanding challenges that remain to be addressed. The term ‘regenerative medicine’ encompasses strategies for restoring or renewing tissue or organ function by: (i) in vivo tissue repair by in-growth of host cells into an acellular natural or synthetic biomaterial, (ii) implantation of tissue ‘engineered’ in vitro by seeding cultured cells into a biomaterial scaffold, and (iii) therapeutic cloning and stem cell-based tissue regeneration. In this article, we review recent developments underpinning the emerging science of regenerative medicine and critically assess where successful implementation of novel regenerative medicine approaches into urology practice might genuinely transform the quality of life of affected individuals. We advocate the need for an evidence-based approach supported by strong science and clinical objectivity. KEYWORDS regenerative medicine, tissue engineering, stem cells, biomaterial, urothelium, bladder reconstruction INTRODUCTION Tissue engineering has been defined as the application of biological and engineering principles to construct functional tissues to supplement or replace diseased or defective body parts. More recently, the broader term of ‘regenerative medicine’ has been coined to encompass the creation, replacement and repair of tissues or organs by a range of therapeutic strategies. Accepted for publication 19 January 2011 In this article, we review recent developments underpinning the emerging science of regenerative medicine and consider current and potential future applications of regenerative medicine within urology, with particular reference to lower urinary tract reconstruction. Regenerative medicine has attracted extensive media interest ranging from informed analysis, to coverage that has more in common with science fiction. Within the scientific and clinical communities, the excitement engendered by the initial promise of regenerative medicine has unfortunately prompted exaggerated claims by some researchers and more worryingly, examples of culpable misconduct and scientific fraud. For this reason, we will endeavour to provide a critical assessment of the current status and therapeutic potential of regenerative medicine in