This article was taken from the March 2014 issue of Wired magazine. Be the first to read Wired's articles in print before they're posted online, and get your hands on loads of additional content by subscribing online.
For all their medical promise, stem cells often come with a lot of ethical baggage -- human embryos are required for production. A new generation is worry-free: adult cells reprogrammed to an embryonic-like state. These induced pluripotent stem cells (iPSCs) offer "master" cells for projects such as lab-grown organs. "iPSCs are part of a revolution in stem-cell-based medicine," says Paul Knoepfler, a stem cell biologist at the University of California, Davis, and author of Stem Cells: An Insider's Guide (World Scientific, 2013).
Recent advances include making patient-specific human embryonic stem cells (ESCs) without destroying embryos, and skipping the pluripotent stage by converting adult cells from one type to another. Here are six research groups making progress.
Harvard University, US
Harald Ott
Ott's team stripped down a dead rat heart to leave a scaffold of structural proteins, which they seeded with cells from newborn rats. After ten days in a chamber that mimics biological conditions, this amalgam had developed into a rudimentary heart.
What's next: getting iPSCs to reproduce human heart cells.
Peking University, China
Hongkui Deng
Earlier this year, Deng's team found a way to make iPSCs from adult mouse cells using only a cocktail of chemicals. If the approach works with human cells, it could provide a safer alternative to conventional reprogramming.
What's next: a mix of compounds that will work on human cells.
RIKEN Center for Developmental Biology, Japan
Masayo Takahashi
Takahashi is trying to halt age-related macular degeneration in humans, which can lead to blindness, by inserting healthy retinal cells derived from iPSCs into the eyes of patients. The iPSCs will be genetically identical to the patient's cells.
What's next: full clinical trials of an iPSC-based therapy.
Oregon Health and Science University, US
Shoukhrat Mitalipov
Before iPSCs, cloning was the best hope for creating genetically matched cells for therapy. Mitalipov's team created human ESCs by transferring the nucleus of a donor cell - a fetal skin cell - to an egg cell whose nucleus had been removed.
What's next: human iPSC/ESCs checks for abnormalities.
Stanford University, US
Marius Wernig
Rather than reprogram cells into a pluripotent state, Wernig's team used three transcription factors to transform adult mouse skin cells into functional brain cells. Skipping the pluripotent stage takes out the risk of creating tumours via extreme proliferation.
What's next: getting the technique to work on human cells.
University of Cambridge, UK
Ludovic Vallier
In 2010, Vallier and his colleagues cajoled human iPSCs into functional liver cells - a technique that could provide large quantities of patient-specific cells. In 2011, they corrected a gene mutation responsible for liver cirrhosis in iPSCs that matured into healthy cells.
What's next: finding genetic variations in a range of diseases.
This article was originally published by WIRED UK
