Two stem cell researchers won the Nobel Prize in Physiology or Medicine today for their discovery that adult cells can be reprogrammed into pluripotent stem cells, a finding which has advanced the field of developmental biology and has potential therapeutic applications.
“It is particularly pleasing to see how purely basic research, originally aimed at testing the genetic identity of different cell types in the body, has turned out to have clear human health prospects,” Gurdon told the BBC.
Performed more than four decades apart, the experiments conducted by these two men led to the development of iPSCs, which have many properties that are similar to stem cells extracted during embryogenesis.
In 1962, Gurdon questioned whether or not the genome of differentiated cells could still promote the development of different cell types. Using nuclear transplantation techniques that he developed at Oxford University, he replaced the nucleus of an egg cell of a frog with one that was extracted from an adult cell of the same species. As a result, Gurdon observed that the egg cell with the transplanted adult-cell nucleus still developed into a frog (1).
More than 40 years later, Yamanaka’s work furthered this concept by demonstrating that differentiated mammalian cells could be made pluripotent simply by introducing a couple of protein factors. In 2006, Yamanaka reprogrammed adult mouse skin cells into iPSCs by introducing four factors: Oct ¾, Sox2, c-Myc, and Klf4 (2). In 2007, he went on to show that same approach could be used to induce pluripotency in human adult skin cells (3).
Since then, these iPSCs have not only become important research tools for those studying developmental biology but also have been recognized for their potential in cell therapies. Because some have questioned the ethics of embryonic stem cell (ESCs) research, iPSCs have become a viable alternative.
Yamanaka said: “My goal, all my life, is to bring this stem cell technology to the bedside, to patients, to clinic.”
Most recently, researchers have used these reprogramming techniques to generatefunctionalmouseeggcells that then were used to produce living pups.
1. Gurdon, J. B. 1962. The developmental capacity of nuclei taken from intestinal epithelium cells of feeding tadpoles. Journal of Embryology and Experimental Morphology 10(4):622-640.
2. Takahashi, K., and S. Yamanaka. 2006. Induction of pluripotent stem cells from mouse embryonic and adult fibroblast cultures by defined factors. Cell 126(4):663-676.
3. Takahashi, K., K. Tanabe, M. Ohnuki, M. Narita, T. Ichisaka, K. Tomoda, and S. Yamanaka. 2007. Induction of pluripotent stem cells from adult human fibroblasts by defined factors. Cell 131(5):861-872.