Stem cells as role models for reprogramming and repair.

Stem cells are a promising source for cellular therapies across many diseases and tissues. Their inherent ability to differentiate into other cell types has been the focus of investigation over decades. This ability is currently being exploited for therapies using strategies to repair or replace damaged tissues and cells or to alleviate immune rejection. Exploring stem cell function has enabled direct reprogramming approaches, for example, through the production of induced pluripotent stem cells and the generation of tissue-specific stem cells. Understanding stem cell function has emerged as an important strategy for repopulating stem cell pools or generating differentiated cells for therapy. Here, we review general principles of mammalian stem cell biology and cellular reprogramming approaches and their use for current and future therapeutic purposes.