Cell Programming for Future Regenerative Medicine

Abstract

Numerous diseases are characterized by malfunction of key cells or their faulty integration within highly complex organ systems. Intense research over the last decade has led to a better understanding of these disorders on the molecular level. This is an indispensable prerequisite for restoring the functionality of the affected organs, representing the first and foremost aim of the rapidly developing field of regenerative medicine. However, adult organs exhibit limited self-renewal capacity and often cannot accomplish a functional restoration on their own. Therefore, new strategies are currently being considered for cell programming based replacement therapies as well as for disease modelling and drug development. Before the discovery that somatic cells could be either reprogrammed to a pluripotent state or directly converted to other somatic cell types, the regenerative field was hampered by ethical concerns connected to human embryonic stem cells as well as by restricted availability of adult stem cells. Meanwhile, several strategies based on the introduction of lineage specific transcription factors, mRNAs, microRNAs and small molecules have opened up new perspectives for safe and efficient generation of induced pluripotent stem cells (iPSCs) as well as various specified somatic cell types. The foremost priority should be the generation of fully functional cells with characteristics as close as possible to their natural counterparts. Furthermore, the production of clinically relevant numbers of healthy cells as well as cells with defined disease patterns could provide an important link between basic research, drug screening and safety testing and ultimately clinical trials. In this article we summarize the remarkable recent successes in cellular reprogramming, which have highly contributed to the great progress of regenerative medicine over the last years.