Human iPSC technology, which has evolved rapidly since 2007 (Box 1), has ushered in an exciting new era for the fields of stem cell biology and regenerative medicine, as well as disease modeling and drug discovery. Soon after the development of the technology, human iPSCs were rapidly applied to generate human ‘disease-in-a-dish’ models and used for drug screening for both efficacy and potential toxicities. Such approaches are now becoming increasingly popular, given the surge of interest in phenotypic screening and the advantages of human iPSCs in disease modeling, compared with traditional cellular screens. These advantages include their human origin, easy accessibility, expandability, ability to give rise to almost any cell types desired, avoidance of ethical concerns associated with human ESCs, and the potential to develop personalized medicine using patient-specific iPSCs. Furthermore, recent advances with gene-editing technologies — in particular the CRISPR/Cas9 technology — are enabling the rapid generation of genetically defined human iPSC-based disease models. iPSCs are also a key component of an emerging generation of more physiologically representative cellular platforms incorporating three dimensional (3D) architectures and multiple cell types.
