iPSCs: 10 Years and Counting

Embryos, fetuses, and neonates form perfectly functional tissues and organs every day. Despite fevered efforts over the past 30 years, there has been very modest progress toward achieving the bewitching goal of organ replacement with embryonic or iPSCs. What is the basis of this humbling status quo? Surely one reason is our enduring ignorance of mechanisms governing development in any organ or cell. For organs like pancreatic islets, developmental studies have revealed dozens of crucial conditions or factors required to create a functional islet. It is likely there are thousands more to discover from integrated studies of organ development and physiology. Embryology, developmental and transplant biology, genetics, physiology, and other disciplines fostered the invention of iPSCs and embryonic stem cells. We should re-dedicate ourselves to the unfinished work that the pioneers in these disciplines, like Morgan, Spemann, Mangold, Jacob, Monod, Medawar, and Claude Bernard, have thus far advanced. We should avoid an impatient, jackpot mentality that has adapted what little we know to generate imperfect replacement organs from renewable sources. What would Dr. Bernard suggest? Perhaps that, to achieve the lofty goal of functional organ replacement with stem cells, it would be useful to remain patiently dedicated to our basic scientific foundations. Reprogramming for All